.###
     Compressed volume file (DoubleSpace)
 .###
     Temp file (QTIC)
 .#24
     Printer data file for 24 pin matrix printer (LocoScript)
 .#gf
     Font file (MetaFont)
 .#ib
     Printer data file (LocoScript)
 .#sc
     Printer data file (LocoScript)
 .#st
     Standard mode printer definitions (LocoScript)


$

 .$$$
      Temporary file
 .$$f
      Database (OS/2)
 .$$p
      Notes (OS/2)
 .$$s
      Spreadsheet (OS/2)
 .$00
      Pipe file (DOS)
 .$1
      ZX Spectrum file in HOBETA format
 .$d$
      Data (OS/2 Planner)
 .$db
      Temporary file (dBASE IV)
 .$ed
      Editor temporary file (MS C)
 .$ln
      TLink response file (Borland C++)
 .$o1
      Pipe file (DOS)
 .$vm
      Virtual manager temporary file (Windows 3.x)


&

 .&&&
       Temporary file


)

 .)2(
     LHA archiver temporary file (LHA)


0

 .0
     Compressed harddisk data (DoubleSpace)
 .000
     Common filename extension (GEOS)
 .000
     Compressed harddisk data (DoubleSpace)
 .001
     Fax (Hayes JT FAX) (many)
 .075
     75x75 dpi display font (Ventura Publisher)
 .085
     85x85 dpi display font (Ventura Publisher)
 .091
     91x91 dpi display font (Ventura Publisher)
 .096
     96x96 dpi display font (Ventura Publisher)
 .0b
     Printer font with lineDraw extended character set (PageMaker)


1

 .1
      Unformatted manual page (Roff/nroff/troff/groff)
 .10x
      Bitmap graphics (Gemini 10x printer graphics file)
 .123
      Data (Lotus123 97)
 .12m
      Smartmaster file (Lotus123 97)
 .15u
      Printer font with PI font set (PageMaker)
 .1st
      Usually README.1ST text


2

 .24b
     Bitmap graphics (24bit data)
 .286
     Virtual device driver (Windows standard mode)
 .2gr
     VGA graphics driver (Windows Video grabber)


3

 .301
      Fax (Super FAX 2000 - Fax-Mail 96))
 .386
      Virtual device driver (Windows 386 enhanced mode)
 .3d2
      3D data (Atari Stereo CAD-3D 2.0)
 .3dm
      QuickDraw 3D Metafile (QuickDraw)
 .3dmf
      QuickDraw 3D Metafile (QuickDraw)
 .3ds
      Graphics (Autodesk 3D Studio)
 .3fx
      3D effects (CorelChart)
 .3gr
      VGA graphics driver (Windows Video grabber)
 .3t4
      Binary file converter to ascii (Util3)


4

 .4c$
      Datafile (4Cast/2)
 .4ge
      Compiled source code (Informix 4GL)
 .4gl
      Informix 4GL language source code file
 .4md
      Musical file
 .4sw
      Swap file (4DOS)
 .4th
      Forth language source code file (ForthCMP - LMI Forth)


6

 .668
      Music (the mixing is always at 12048Hz)
 .669
      Music (8 channels MOD) (669 Composer)
 .6cm
      Music (6 Channel Module) (Triton FastTracker)


7

 .75
     75x75 dpi display font (Ventura Publisher)
 .777
     Compressed file archiver (777)


8

 .8
       Assembly language source code file (A86)
 .85
       85x85 dpi display font (Ventura Publisher)
 .8cm
       Music (8 Channel Module) (Triton FastTracker)
 .8m
       Math 8 extended character set printer font (PageMaker)
 .8med
       Music (Amiga OctaMed)
 .8svx
       Sound (Amiga 8-bit)
 .8u
       Roman 8 extended character set printer font (PageMaker)


9

 .91
    91x91 dpi display font (Ventura Publisher)
 .96
    96x96 dpi display font (Ventura Publisher)


@

 .@@@
        Screen files used in installation or instructions


S

 .S
   Assembly language source code file.S for cpp (Unix)


Z

 .Z
   Compressed file archive.Z (ascii) (compress)


_

 .___
     Table (Adinf)


a

 .a
        Ada language source code file
 .a
        Assembly source code (Macintosh)
 .a
        Object library (unix)
 .a11
        Graphics (AIIM)
 .a8
        Alpha channel image data (24bit 3D animation) (Cubicomp PictureMaker)
 .a86
        Assembly language source code file (A86)
 .ab6
        Datafile (ABStat)
 .ab8
        Datafile (ABStat)
 .abc
        Document (ABC FlowCharter 1.0)
 .abc
        General filename extension (ABC programming language)
 .abc
        Musical notation language file (folk melodies)
 .abf
        Adobe Binary Screen Font (Adobe Software)
 .abk
        Automatic backup (CorelDraw)
 .abk
        Avigo Backup (Avigo)
 .abm
        Album (Image PALS, PhotoPlus)
 .abr
        Adobe Brush file (Adobe PhotoShop)
 .abs
        Abstracts (info file)
 .abs
        Data file (Abscissa)
 .ac$
        Spooled plot file (AutoCAD AutoSpool)
 .aca
        Project (Project Manager Workbench)
 .acad
        AutoCAD database file
 .acb
        Compressed file archive (ACB)
 .acb
        Graphics (ACMB)
 .acc
        Program (DR-DOS - ViewMax) (GEM / resident)
 .ace
        Compressed file archive (ACE, WinACE)
 .acf
        Adobe Custom Filter (Adobe PhotoShop)
 .acgi
        ACGI Script (WWW)
 .acl
        Keyboard accelerator (Corel Draw 6)
 .acm
        Audio Compression Module add-on (Windows)
 .acm
        Graphics file (ACMB format)
 .acmb
        Graphics file (ACMB format)
 .aco
        Adobe Color Palette
 .acp
        Assistant preview file (Ms Office)
 .acp
        Compressed file archive (ACB)
 .acr
        Bitmap graphics (ACR-NEMA medical image file)
 .act
        Actor source code file (Graphics cell) (Animation Works)
 .act
        Assistant actor (MS Office)
 .act
        Color table (Adobe Photoshop)
 .act
        Foxdoc Action Diagrams (FoxPro)
 .act
        Presentation (Action!)
 .acv
        Compress and decompress audio data (OS/2 driver)
 .ad
        Screensaver (AfterDark)
 .ad2
        ADPCM 2-bit compressed voice file (ZFAX)
 .ad3
        ADPCM 3-bit compressed voice file (ZFAX)
 .ada
        Ada language source code file
 .adb
        Ada Package Body
 .adb
        Appointment database (HP 100LX organizer)
 .adc
        Bitmap graphics (16 colors) (ScanStudio)
 .adc
        Dictionary (Lingvo)
 .adc
        Sound (TI/MIT ADC format)
 .add
        Adapter Device Driver (OS/2)
 .adex
        Bitmap graphics (ADEX Corp. image file)
 .adf
        Administration configuration file
 .adf
        Amiga Disk File
 .adi
        Graphics (AutoCAD Device-Independent binary plotter image)
 .adl
        Mca adapter description library (QEMM)
 .adm
        MultiModule screensaver (AfterDark)
 .adn
        Add-in (Lotus 1-2-3)
 .adp
        Dynamite file (Astound)
 .adp
        Setup file for fax modem interaction (FaxWorks)
 .adpcm
        Sound (Intel/DVI Adaptive Differential Pulse Code Modulation format)
 .adr
        Randomizer screensaver (AfterDark)
 .ads
        Ada Package Specification
 .adt
        Datafile for cardfile application (HP NewWave)
 .adt
        Dictionary (Lingvo)
 .adt
        Fax (AdTech)
 .adv
        GUS device driver (Gf166.com)
 .adx
        Document (Archetype Designer)
 .adx
        Index (Approach)
 .aex
        Alpha linked executable file 
 .aex
        Armored extracted public key (PGP)
 .aexpk
        Armored extracted public key (PGP)
 .af2
        Flowchart (ABC FlowCharter 2.0)
 .af3
        Flowchart (ABC FlowCharter 3.0)
 .afc
        Apple sound
 .afi
        Bitmap graphics (Truevision)
 .afl
        Font file (for Allways) (Lotus 1-2-3)
 .afl
        RubberFlex animation (AnimaFlex)
 .afm
        Adobe Font Metrics (Type 1 font metrics for font installers)
 .afm
        Datafile for cardfile application (HP NewWave)
 .afp
        Shape palette (ABC FlowCharter)
 .aft
        Template (ABC FlowCharter 3.0)
 .afw
        Workspace (ABC FlowCharter 3.0)
 .agn
        Agenda (Psion Series 3)
 .ai
        Vector graphics (Adobe Illustrator)
 .aif
        AIFF sound (Apple Audio Interchange Format File)
 .aif
        Application information file (EPOC)
 .aif
        Setup information (ADW Knowledge Ware)
 .aifc
        AIFF-C sound (Apple Audio Interchange Format File with Compression)
 .aiff
        AIFF sound (Apple Audio Interchange Format File)
 .aim
        AOL Instant Message Launch (Netscape)
 .aim
        Asm Text Mode Image File (The Ultimate Draw)
 .ain
        Compressed file archive (Ain)
 .aio
        APL file transfer format file
 .air
        Automatic image registration
 .ais
        Graphics (Array of Intensity Samples) (Xerox)
 .ais
        Image sequence file (ACDSee)
 .aix
        Datafile for cardfile application (HP NewWave)
 .al
        Sound (ALAW format)
 .alb
        Graphics album (JASC Image Commander)
 .alg
        Activity Log (ARCSOLO)
 .alias
        Bitmap graphics (24bit RGB RLE) (Alias image file)
 .all
        Arts & Letters Library (Symbol and font files)
 .all
        Filelist of all files (FRQView)
 .all
        Format file for working pages (Always)
 .all
        General printer information (WordPerfect for Win)
 .alo
        Almanac support file
 .alpha
        Bitmap graphics (raw alpha bytes)
 .als
        Bitmap graphics (24bit RLE) (Alias - Vivid RayTracer)
 .alt
        Menu file (WordPerfect Library)
 .amf
        Music (Advanced Module Format)
 .amg
        Compressed file archive (AMGC)
 .amg
        System image file (Actor)
 .ams
        Adobe Monitor Setup calibration file (Adobe PhotoShop)
 .ams
        Music (Velvert Studio MOD)
 .anc
        List of pattern colors (Canon Computer Pattern Maker)
 .ani
        Animated cursor (Windows 95/NT)
 .ani
        Animation (Presidio - many)
 .anm
        Animation (Deluxe Paint Animator)
 .ann
        Help annotations (Windows 3.x)
 .ans
        Animation (graphics or text)
 .ans
        Ascii text with ANSI character set (NewWave Write)
 .ant
        Game data (SimAnt)
 .aol
        America On-Line related file
 .aos
        Installable program (Nokia Communicator add-on software)
 .ap
        Compressed Amiga file archive (Whap)
 .ap
        Datafile (Datalex EntryPoint 90)
 .apc
        Printer driver characters (Lotus 1-2-3)
 .apd
        Aldus Printer Description (Aldus PageMaker)
 .apd
        Printer driver (Lotus 1-2-3)
 .apf
        Printer driver fonts (Lotus 1-2-3)
 .api
        Adobe Printer Ink file (Adobe PhotoShop)
 .api
        Application Program Interface file (Adobe Acrobat)
 .api
        Passed parameter file (1st Reader)
 .api
        Printer driver (Lotus 1-2-3)
 .apl
        APL work space
 .apl
        Support module (Manugraphics APL products)
 .app
        Add-in application file (Symphony)
 .app
        Application object file (dBASE Application Generator)
 .app
        Executable application file (DR-DOS - NeXTstep - Atari - EPOC)
 .app
        Generated application (FoxPro)
 .apr
        Data (Lotus Approach 97)
 .apr
        Employee performance review (Employee Appraiser)
 .apx
        AppExpert database file (Borland C++ 4.5)
 .arc
        Compressed file archive (ARC - PKARC - QUARK - SQUASH)
 .arf
        Automatic Response File
 .arh
        Archivers definitions file (DN)
 .ari
        Audio (Aristotle)
 .ari
        Compressed file archive (ARI)
 .arj
        Compressed file archive (Robert Jung's ARJ)
 .ark
        ARC archive (CP/M port of ARC file archiver)
 .ark
        Archive (Managing your Money)
 .ark
        Compressed file archive (QUARK)
 .arr
        Arrangement (Atari Cubase)
 .arr
        Bitmap graphics (Amber ARR image)
 .art
        Bitmap graphics (B&W) (many - First Publisher - Xara Studio)
 .art
        Graphics (Another Ray Tracer - Vort)
 .arx
        Compressed file archive (ARX)
 .asc
        Armored encrypted file (Pretty Good Privacy)
 .asc
        Ascii text
 .asc
        Bitmap graphics B&W ASCII (GROB Graphic Object) (HP-48sx calculator)
 .asd
        Autosave file (Word for Windows)
 .asd
        Presentation (Astound)
 .asd
        Screen driver (Lotus 1-2-3)
 .asf
        Datafile (STATGRAPHICS)
 .asf
        Screen font (Lotus 1-2-3)
 .asf
        Video (Advanced Streaming Format) (WWW)
 .ash
        Assembly language header file (TASM 3.0)
 .asi
        Assembler include file (Turbo C - Borland C++)
 .asic
        ASIC language source code file (ASIC)
 .asm
        Assembly language source code file
 .aso
        Assembler object (object orientated) file (Turbo Assembler)
 .aso
        Astound Dynamite Objects
 .asp
        Active Server Page (HTML file with Microsoft IIS script)
 .asp
        Aspect language script file (Procomm Plus)
 .asp
        Association of Shareware Professionals note
 .ast
        Adobe Color Separtion table (Adobe PhotoShop)
 .ast
        Assistant file (Claris Works)
 .ast
        Astound multimedia file
 .asx
        Cheyenne Backup script
 .asx
        Video (Advanced Streaming Format) (WWW)
 .at2
        Auto template (Aldus Persuasion 2.0)
 .atk
        Bitmap graphics (Andrew Toolkit Raster Object file)
 .atm
        Adobe Type Manager related file
 .att
        Bitmap graphics (AT&T Group 4)
 .au
        Sound - basic 8bit ulaw compressed audio file (Sun Audio File format)
 .aut
        Automation (IPIX)
 .aux
        Auxiliary dictionary (ChiWriter)
 .aux
        Auxillary references (TeX/LaTeX)
 .ava
        Publication (Avagio)
 .avb
        AntiViral Toolkit Pro Bases
 .avi
        Audio Video Interleaved (movie) (Video for Windows)
 .avr
        Sound (Audio Visual Research file format)
 .avs
        Application Visualization System (animation)
 .avs
        Bitmap graphics (AVS X image file)
 .avt
        Avatar-coding files (A3E)
 .aw
        Text document (HP AdvanceWrite)
 .awa
        Animation Works Accelerated movie (Animation Works)
 .awd
        Document (FaxView - Microsoft Fax At Work)
 .awk
        AWK language source code file
 .awm
        Animations Works Movie (Animation Works)
 .aws
        Data (STATGRAPHICS)
 .awx
        Custom application wizard
 .ax
        Linker information for libraries (Modula-3)


b

 .b
        BASIC language source code file
 .b
        Base program (Modula-3)
 .b
        Batch list (APPLAUSE)
 .b&w
        Bitmap graphics (Mono binary screen image) (1st Reader)
 .b&w
        Bitmap graphics (black and white) (atari - mac)
 .b1n
        Bitmap graphics (both mono and color binary screen image) (1st Reader)
 .b30
        Printer font (JLaser - Cordata) (Ventura Publisher)
 .b4
        Nuts and Bolts file (Helix)
 .b64
        Encoded file archive (ascii) (base64 MIME)
 .b8
        Bitmap graphics (one byte per pixel) plane two (PicLab)
 .b8
        Red channel image data (24bit 3D animation) (Cubicomp PictureMaker)
 .b_w
        Bitmap graphics (black and white) (atari - mac)
 .bac
        Backup
 .bad
        Bad file (Oracle)
 .bak
        Backup
 .bal
        Music score (Ballade)
 .bar
        Compressed file archive (Unix BAR archive)
 .bar
        Horizontal bar menu object file (dBASE Application Generator)
 .bas
        BASIC language source code file (QuickBASIC - GW-BASIC)
 .bat
        Batch file (DOS)
 .bb
        Database backup (Papyrus)
 .bbl
        Bibliographic reference (TeX/BibTeX)
 .bbm
        Brush (Deluxe Paint)
 .bbnng
        Bitmap graphics (BBN BitGraph terminal Display Pixel Data (DPD) sequence)
 .bbp
        Bezier surface file
 .bbs
        Bulletin Board System announce or text info
 .bbs
        Hudson-style messagebase (FTN software)
 .bch
        Batch process object file (dBASE Application Generator)
 .bch
        Datafile (Datalex EntryPoint 90)
 .bck
        Backup (VMS/VAX)
 .bcm
        Comms script backup (MS Works)
 .bco
        Outline font description (Bitstream)
 .bcp
        Makefile (Borland C++)
 .bcs
        Browse information (Windows95)
 .bct
        Backup dictionary (Clarion)
 .bcw
        Workspace (Environment settings) (Borland C++ 4.5)
 .bdb
        Database backup (MS Works)
 .bdc
        Dictionary (Lingvo)
 .bdf
        Binary update file (BUpdate)
 .bdf
        Bitmap Distribution Format file (font - glyph) (Adobe - X11)
 .bdf
        Datafile (Egret)
 .bdr
        Border (MS Publisher)
 .bdt
        Dictionary (Lingvo)
 .bex
        Binary extracted public key (PGP)
 .bexpk
        Binary extracted public key (PGP)
 .bez
        Bezier surface file
 .bez
        Outline font description (Bitstream)
 .bf2
        Bradford 2 font
 .bfc
        Briefcase (Windows 95)
 .bfm
        Font metrics (unix/Frame)
 .bfx
        Fax (BitFax)
 .bg
        Game (Backgammon for Windows)
 .bga
        Bitmap graphics (OS/2)
 .bgi
        Device driver (Borland Graphics Interface)
 .bhx
        Compressed file ascii archive (BinHex)
 .bi
        BASIC source code include file (Visual Basic)
 .bib
        Bibliography (ascii)
 .bib
        Database - not compatible with TeX format (Papyrus)
 .bib
        Literature database (TeX/BibTeX)
 .bif
        Binary Information File (ASCII file describing image)
 .bif
        Bitmap graphics (b&w Binary Image Format) (Image Capture board)
 .bif
        Initialization file (GroupWise)
 .biff
        XLITE 3D file
 .big
        Chinese text (old version)
 .big5
        Chinese text (old version)
 .bil
        Satellite image (8bit GIS tape format) (SPOT image)
 .bin
        Binary file
 .bin
        SGI Powerflip
 .bio
        BIOS (OS/2)
 .bit
        Bitmap graphics (X11)
 .bix
        Compressed file archive (BIX)
 .bk
        Faxbook (JetFax)
 .bk!
        Document backup (WordPerfect for Win)
 .bk1
        Timed backup file for document window 1 (WordPerfect for Win)
 .bk2
        Timed backup file for document window 2 (WordPerfect for Win)
 .bk3
        Timed backup file for document window 3 (WordPerfect for Win)
 .bk4
        Timed backup file for document window 4 (WordPerfect for Win)
 .bk5
        Timed backup file for document window 5 (WordPerfect for Win)
 .bk6
        Timed backup file for document window 6 (WordPerfect for Win)
 .bk7
        Timed backup file for document window 7 (WordPerfect for Win)
 .bk8
        Timed backup file for document window 8 (WordPerfect for Win)
 .bk9
        Timed backup file for document window 9 (WordPerfect for Win)
 .bki
        Backup index (IBM BookManager)
 .bkp
        Backup file (Write - TurboVidion DialogDesigner)
 .bks
        Bookself (IBM BookManager)
 .bks
        Worksheet backup (MS Works)
 .bkw
        Mirror image of font set (FontEdit)
 .bld
        Bloadable picture (BASIC)
 .blg
        Backup Log (ARCSOLO)
 .blg
        BibTex log
 .blk
        Temporary file (WordPerfect for Win)
 .bm
        Bitmap graphics (1bit text) (X Window BitMap)
 .bm1
        Game data (Apogee BioMenace)
 .bmf
        Graphics (Binary Material Format) (Corel)
 .bmk
        Bookmark file (Windows)
 .bmp
        Bitmap graphics (PC Paintbrush - many)
 .bmt
        Ami Pro Button (Ami Pro)
 .bnk
        Adlib instrument bank file
 .bnr
        Graphics Banner (Banner - Poster)
 .bob
        Bitmap graphics (BOB Image file)
 .boo
        Book (IBM BookManager)
 .boo
        Bootstrap (Kermit protocol binary file)
 .boo
        Encoded file archive (ascii) (Boo)
 .book
        Book (Adobe FrameMaker)
 .boz
        Compressed file archive (bzip over zip)
 .bpc
        Chart (Business Plan Toolkit)
 .bpp
        Backup application (Clarion)
 .bps
        Text document backup (MS Works)
 .bpt
        Bitmap master file (CorelDraw)
 .br
        Data (Omnis7)
 .br
        Script (Bridge)
 .brd
        Eagle Layout File
 .brk
        Fax (Brooktrout Fax-Mail)
 .brk
        Mailer REXX script (The Brake!)
 .brl-cad
        Ballistic Research Laboratory CAD
 .brush
        Bitmap graphics (Xerox Doodle Brush file)
 .brx
        A file for browsing an index of multimedia options 
 .bs1
        Game data (Apogee Blake Stone)
 .bs2
        Archive (BS2)
 .bsa
        Compressed file archive (BSArc)
 .bsc
        Browser information (MS Developer Studio)
 .bsc
        Compressed Apple II file archive (BINSCII)
 .bsc
        Database (Source Browser)
 .bsc
        Pwbrmake object file (MS Fortran)
 .bsp
        Map (Quake)
 .bst
        BiblioTex Style (BibTeX)
 .bsy
        Busy flag (FTN soft)
 .btl
        Inmos bootable file 
 .btm
        Batch file (Batch To Memory) (4DOS - NDOS)
 .btn
        Button file (Makeover)
 .bub
        Photobubble (IPIX)
 .bufr
        Binary Universal Form for the Representation
 .bufr
        Meteorological Data
 .bug
        Bugs and Problems
 .bun
        Bundle file (CakeWalk Audio)
 .bup
        Backup
 .but
        Button definitions (Buttons!)
 .bv1
        Overflow file below insert point in Doc 1 (WordPerfect for Win)
 .bv2
        Overflow file below insert point in Doc 2 (WordPerfect for Win)
 .bv3
        Overflow file below insert point in Doc 3 (WordPerfect for Win)
 .bv4
        Overflow file below insert point in Doc 4 (WordPerfect for Win)
 .bv5
        Overflow file below insert point in Doc 5 (WordPerfect for Win)
 .bv6
        Overflow file below insert point in Doc 6 (WordPerfect for Win)
 .bv7
        Overflow file below insert point in Doc 7 (WordPerfect for Win)
 .bv8
        Overflow file below insert point in Doc 8 (WordPerfect for Win)
 .bv9
        Overflow file below insert point in Doc 9 (WordPerfect for Win)
 .bw
        Bitmap graphics (SGI image)
 .bwb
        Spreadsheet application (Visual Baler)
 .bwr
        Beware (buglist) (Kermit)
 .byu
        Bitmap graphics (Movie BYU format)
 .bz
        Compressed file archive (bzip)
 .bz2
        Compressed file archive (bzip2)


c

 .c
        C language source code file
 .c
        Compressed unix file archive (compact)
 .c++
        C++ language source code file
 .c--
        C-- language source code file (Sphinx C--)
 .c00
        Print file (Ventura Publisher)
 .c4
        Bitmap graphics (1bit) (JEDMICS CCITT4 format)
 .c64
        Bitmap graphics (Commodore 64 image file)
 .c86
        C language source code file (Computer Innovation C86)
 .ca
        Initial cache data for root domain servers (Telnet)
 .ca0
        Packed and splitted file (Borland Installer)
 .ca7
        Job file (Beta 44)
 .cab
        Compressed Cabinet file (Microsoft)
 .cac
        dBASE IV executable when caching on/off (see cachedb.bat)
 .cad
        Document (Drafix Windows CAD)
 .cal
        Bitmap graphics B&W (Computer-aided Acquisition and Logistics Support)
 .cal
        Calendar file (Windows 3.x)
 .cal
        Spreadsheet (SuperCalc)
 .cals
        Bitmap graphics (Computer Aided Acquisition and Logistics Support)
 .cam
        Graphics (Casio QV Digital Camera)
 .can
        Fax (Navigator Fax)
 .cap
        Caption (Ventura Publisher)
 .cap
        Compressed music file
 .cap
        Session capture file (ProComm - Telix)
 .cas
        C + ASM language source (Turbo C)
 .cat
        Catalog (CP Backup - dBASE IV)
 .cat
        IntelliCharge categorization file (Quicken)
 .cat
        Logical package (Rational Rose)
 .cb
        Microsoft clean boot file
 .cbc
        Fuzzy logic system (CubiCalc)
 .cbl
        Cobol language source code file
 .cbm
        Compiled bitmap graphics (XLib)
 .cbs
        Button bar configuration file (MasterWord)
 .cbt
        Computer Based Training (many)
 .cc
        C++ language source code file (gcc)
 .cc
        CC language source code file (cc)
 .cca
        Data (cc:Mail)
 .ccad
        Data (ClarisCAD)
 .ccb
        Animated Button configuration (Visual Basic)
 .ccc
        Bitmap graphics (native format) (Curtain Call)
 .ccf
        Communications configuration file (Symphony)
 .ccf
        Configuration file (OS/2 Multimedia Viewer)
 .cch
        Chart (CorelChart)
 .cci
        CCITT Group 3 and Group 4 Encoding
 .ccitt
        CCITT Group 3 and Group 4 Encoding
 .ccl
        Communication Command Language file (Intalk)
 .ccm
        Mailbox (Lotus CC:Mail)
 .cco
        Btx Graphics file (XBTX)
 .cco
        Data (CyberChat)
 .ccrf
        Bitmap graphics (Calcomp Raster File) (B&W or 1bit CMYK for printers)
 .cct
        Shockwave cast (Macromedia Director)
 .cd
        CD description (DN)
 .cda
        CD audio track
 .cdb
        Card database (CardScan)
 .cdb
        Main database (Turbo C Utilities)
 .cdf
        Channel Definition Format (Microsoft)
 .cdf
        Common Data Format (multi-dimensional data sets)
 .cdf
        Cyberspace Description Format
 .cdf
        Graphics (Unidata netCDF)
 .cdi
        Compact Disk Interactive (Phillips CD-I IFF file)
 .cdk
        Document (Atari Calamus)
 .cdl
        CAD language file (CADKey)
 .cdm
        Disk Drivers NPA (Novell NetWare)
 .cdm
        Music format (compressed)
 .cdr
        Vector graphics (CorelDraw format)
 .cdt
        Template (CorelDraw)
 .cdx
        Compound index (FoxPro)
 .cdx
        Compressed drawing (Corel Draw)
 .ce
        Computer Eyes (Digital Vision IFF bitmap)
 .cef
        Workbench application (CA Clipper)
 .ceg
        Bitmap graphics (Tempra Show - Edsun Continuous Edge Graphics)
 .cel
        Animation (Autodesk Animator - 3D Studio)
 .cel
        Bitmap graphics (15/32bit) (Lumena CEL file) (Time Arts software)
 .cel
        CIMFast Event Language file
 .cer
        Compilation error messages (Lahey Fortran)
 .cer
        Security certificate
 .cf
        Configuration (imake)
 .cfb
        Comptons Multimedia file
 .cfb
        Inmos binary configuration file 
 .cfg
        Configuration
 .cfl
        Chart (CorelFLOW)
 .cfm
        Template (Cold Fusion)
 .cfn
        Font data (Atari Calamus)
 .cfo
        C Form Object file (Turbo C Utilities)
 .cfp
        Fax (The Complete Fax Portable)
 .cfr
        CFR Guidance (NRC Inspection Manual)
 .cfs
        Inmos configuration file 
 .cft
        CFast graphics file (Disney Animation Studio)
 .cga
        CGA display font (Ventura Publisher)
 .cgi
        Common Gateway Interface script (WWW)
 .cgl
        Error log (CodeGuard)
 .cgm
        Vector graphics (Computer Graphics Metafile format)
 .ch
        Configuration file (OS/2)
 .ch
        Header file (CA Clipper)
 .ch3
        Chart (Harvard Graphics 3.0)
 .ch4
        Presentation (Charisma 4.0)
 .cha
        Chat (IRC data)
 .chat
        Chat (IRC data)
 .chd
        Font descriptor (FontChameleon)
 .chi
        Document (ChiWriter)
 .chk
        Recovered data (ChkDsk, ScanDisk)
 .chk
        Temporary file (WordPerfect for Win)
 .chl
        Configuration History Log
 .chm
        Compiled HTML file
 .chn
        Data (Ethnograph 3)
 .chp
        Chapter file (Ventura Publisher)
 .chr
        Character set (Turbo C - Turbo Pascal)
 .cht
        Chart (Harvard Graphics 2.0 - SoftCraft Presenter)
 .cht
        Interface file for ChartMaster (dBASE)
 .chz
        Compressed file archive (CHARC)
 .cif
        CD Image File (Easy CD Creator)
 .cif
        Chapter information (Ventura Publisher)
 .cif
        Graphics (Caltech Intermediate Format)
 .cif
        IUCr Crystallographic Information File
 .cil
        Clip gallery download package (Art Gallery)
 .cim
        C Text Mode Image File (The Ultimate Draw)
 .cim
        Game data (SimCity 2000)
 .cin
        INI file change control file (OS/2)
 .cix
        Database index (Turbo C Utilities)
 .ck1
        Game data (iD/Apogee Commander Keen 1)
 .ck2
        Game data (iD/Apogee Commander Keen 2)
 .ck3
        Game data (iD/Apogee Commander Keen 3)
 .ck4
        Game data (iD/Apogee Commander Keen 4)
 .ck5
        Game data (iD/Apogee Commander Keen 5)
 .ck6
        Game data (iD/Apogee Commander Keen 6)
 .ckb
        Keyboard mapping (Borland C++ 4.x)
 .cl
        Common LISP language source code file
 .cla
        Source (Clarion)
 .class
        Java bytecode (compiled class - application)
 .clb
        Clipbook template (Super NoteTab)
 .cld
        Clipper debugger configuration file (CA Clipper)
 .clp
        Bitmap graphics (Clip art) (PCPaint - Pictor - Quattro Pro)
 .clp
        Clipboard file (Windows 3.x)
 .clp
        Compiler responce file (CA Clipper)
 .clr
        Color binary screen image (1st Reader)
 .clr
        Color definitions (Photostyler)
 .clr
        Color scheme (Boxer/2)
 .cls
        Class definition file (C++, Visual Basic)
 .cls
        Class module (Visual Basic)
 .clw
        MFC Class Wizard information (MS VC++)
 .cm
        Bitmap graphics (8bit) (Unix Puzzle)
 .cm
        Data (CraftMan)
 .cmb
        Xtree for Windows Button Bar file
 .cmd
        Batch file (REXX) (OS/2)
 .cmd
        Command file (dBASE - Waffle)
 .cmd
        External command menu (1st Reader)
 .cmf
        Corel Metafile
 .cmf
        FM-music file (Creative Music File)
 .cmk
        Card (Card Shop Plus)
 .cml
        CML document (Chemical Markup Language)
 .cmm
        Cmm script (CEnvi)
 .cmp
        Bitmap graphics (Lead CMP compression)
 .cmp
        Calibration map (Photofinish)
 .cmp
        Compressed data (PKWare compression library)
 .cmp
        Data (CraftMan)
 .cmp
        Header file for PostScript printer files (CorelDraw)
 .cmp
        User dictionary (MS Word for DOS)
 .cmrt
        Data (CraftMan)
 .cmu
        Bitmap graphics (Carnegie Mellon University (CMU) Window Manager bitmap Formats)
 .cmuwm
        Bitmap graphics (Carnegie Mellon University (CMU) Window Manager bitmap Formats)
 .cmv
        Animation (CorelMove - CorelDraw 4.0)
 .cmx
        Vector graphics (CorelDraw)
 .cmyk
        Bitmap graphics (raw cyan magenta yellow and black bytes)
 .cnc
        CNC general program data
 .cnf
        Configuration (program - printer setup)
 .cnm
        Windows application menu options and setup file
 .cnq
        Shop file (Compuworks Design)
 .cnt
        Contents tab file (Rational Rose 98)
 .cnv
        Data conversion support file (Word for Windows)
 .cnv
        Temporary file (WordPerfect for Win)
 .cob
        Cobol language source code file
 .cob
        Graphics (Calgari trueSpace2 File Format)
 .cod
        Code definition table (UUPC)
 .cod
        Datafile (Forecast Plus - MS Multiplan - StatPac Gold)
 .cod
        Printer code definition file (Boxer/2)
 .cod
        Program compiled code (FORTRAN)
 .cod
        Source code in assembler with original C code as comments (MS C)
 .cod
        Template source file (dBASE Application Generator)
 .cod
        Videotext file
 .col
        Color palette (Autodesk Animator - many)
 .col
        Spreadsheet (MS Multiplan)
 .com
        Command (memory image of executable program) (DOS)
 .con
        Configuration file (Simdir)
 .conf
        Configuration information (Unix)
 .coo
        Cookie file
 .core
        Bitmap graphics (Core Software Tech CORE IDC file)
 .cpc
        Compressed image (Cartesian Perceptual Compression)
 .cpd
        Fax Cover document
 .cpd
        Script (Complaints Desk)
 .cpe
        Fax Cover document
 .cpf
        Fax (The Complete Fax)
 .cpi
        Bitmap graphics (Colorlab Processed Image)
 .cpi
        Code Page Information file (DOS)
 .cpj
        CeQuadrat CD ProJect file
 .cpl
        Colour palette (Corel)
 .cpl
        Control panel extension (Windows)
 .cpl
        Presentation (Compel)
 .cpp
        C++ language source code file
 .cpp
        Presentation (CA-Cricket Presents)
 .cpr
        Presentation (Corel Presents)
 .cps
        Backup of startup files (QEMM)
 .cps
        Color PostScript
 .cpt
        Bitmap graphics (Corel Photo-Paint)
 .cpt
        Compressed Macintosh file archive (Compact Pro)
 .cpt
        Encrypted memo file (dBASE)
 .cpt
        Template (CA-Cricket Presents)
 .cpx
        Compressed drawing (Corel Presentation Exchange)
 .cpz
        Music text file (COMPOZ)
 .cra
        Advanced crack file (usually text)
 .crd
        Cardfile (Windows 3.x - YourWay)
 .crf
        Bitmap graphics (Calcomp Raster File) (B&W or 1bit CMYK for printers)
 .crf
        Cross-reference (MASM - Zortech C++)
 .crk
        Crack file (usually text)
 .crp
        Encrypted database (dBASE IV)
 .crp
        Run-time presentation (Corel Presents)
 .crs
        File Conversion Resource (WordPerfect 5.1)
 .crt
        Internet security certificate
 .crt
        Terminal settings information (Oracle)
 .cru
        Compressed file archive (CRUSH)
 .csc
        Corel Script
 .csg
        Graph (Statistica/w)
 .cslm
        Bitmap graphics (Zeiss CSLM file)
 .csm
        Precompiled headers (Borland C++ 4.5)
 .csp
        Screen Image (PC Emcee)
 .css
        Cascading Style Sheet (WWW)
 .css
        Datafile (CSS - Stats+ - Statistica)
 .csv
        Adjusted EGA/VGA palette (CompuShow)
 .csv
        Data file (Comma Separated Values format)
 .csy
        Polymorphic DLL (EPOC)
 .ct
        Bitmap graphics (32bit CMYK) (Scitex CT Bitmap) (Scitex scanners)
 .ct
        Bitmap graphics (32bit) (Iris CT format) (Iris printers)
 .ctc
        Control file (PC Installer)
 .ctf
        Character code translation file (Symphony)
 .ctl
        Control file (dBASE IV - Aldus Setup)
 .cts
        Permanent location contents (ABC programming language)
 .ctx
        Ciphertext file (PGP)
 .ctx
        Course TeXt file (Microsoft online guides)
 .cube
        Bitmap graphics (Cubicomp/Vertigo image file) (Cubicomp PictureMaker)
 .cubi
        Bitmap graphics (Cubicomp/Vertigo image file) (Cubicomp PictureMaker)
 .cue
        Microsoft Cue Cards data
 .cuf
        C Utilities Form definition (Turbo C Utilities)
 .cur
        Cursor image resource (Resource Workshop - Watcom Resource Editor)
 .cursor
        Cursor (Sun Cursor file)
 .cut
        Bitmap graphics (Media Cybernetic's Dr.Halo graphics format)
 .cv
        Archive (Corel Versions)
 .cv
        Information screen (Microsoft CodeView)
 .cv4
        Color file (CodeView)
 .cvf
        Compressed volume (SuperStor)
 .cvp
        Cover page (WinFax)
 .cvs
        Bitmap graphics (Canvas drawing)
 .cvt
        Backup file for CONVERTed database file (dBASE IV)
 .cvw
        Color file (CodeView)
 .cweb
        C Web
 .cwk
        Document (ClarisWorks)
 .cwl
        Library (ClarisWOrks)
 .cws
        Stationery (ClarisWorks)
 .cx
        Script (CodeMapper)
 .cxx
        C++ language source code file (Zortech C++, gcc)


d

 .d63
      Commodore 64 emulator disk file
 .dac
      Sound (TI/MIT DAC format) (byte reversed ADC file)
 .dat
      Data file (ASCII or binary - many)
 .dat
      Merge data (WordPerfect)
 .db
      Configuration (dBASE IV - dBFast - MultiEdit)
 .db
      Database (dbVista - Paradox - Smartware - XTreeGold)
 .db$
      Temporary file (dBASE - Modula2)
 .db2
      Database (dBASE II)
 .db3
      Database (dBASE III)
 .dba
      Database (Turbo Prolog - DataEase)
 .dbd
      Business data (Business Insight)
 .dbd
      Debug info (Clarion Modula-2)
 .dbf
      Database file (dBASE III/IV - FoxPro - dBFast - DataBoss)
 .dbg
      Debugger script (DOS debug - Watcom debuger)
 .dbg
      Symbolic debugging information (MS C/C++)
 .dbk
      Database backup (dBASE IV)
 .dbm
      Datafile (DataEase)
 .dbm
      Menu template (DataBoss)
 .dbo
      Compiled program (dBASE IV)
 .dbs
      Datafile (Managing Your Money - ProDas - SQL Windows)
 .dbs
      Printer description file (MS Word - Works)
 .dbt
      Database text (Clipper)
 .dbt
      Foxbase+ style memo (FoxPro)
 .dbt
      Memo file for database w/same name (dBASE IV - dBFast)
 .dbw
      Windows file (DataBoss)
 .dbx
      Graphics (DataBeam image)
 .dca
      Document Content Architecture text file (IBM DisplayWrite)
 .dcf
      Disk image file
 .dcl
      Delphi Component Library (Borland Delphi)
 .dcp
      Data CodePage (OS/2)
 .dcp
      Device code page (OS/2)
 .dcr
      Data (Shockwave - Macromedia Director)
 .dcs
      Bitmap graphics (Quark Desktop Color Separation EPS file) (QuarkXPress)
 .dcs
      Datafile (ACT! Activity Files)
 .dcs
      Desktop Color Separation file
 .dct
      Database dictionary (Clarion Database Developer)
 .dct
      Spell checking dictionary (Clarion - Harvard Graphics 3.0 - Symphony)
 .dcu
      Delphi unit (compiled) (Borland Delphi)
 .dcx
      Bitmap graphics (Multipage PCX - many faxes)
 .dd
      Compressed Macintosh file archive (DiskDoubler)
 .ddb
      Bitmap graphics
 .dde
      Dynamic Data Exchange (binary)
 .ddf
      Database (BTRIEVE)
 .ddi
      Disk image (DiskDupe)
 .ddif
      Bitmap graphics (DEC DDIF file)
 .ddp
      Device Driver Profile file (OS/2)
 .deb
      Debug script (DOS Debug)
 .dec
      Decoded file
 .def
      Assembly header file (Geoworks Esp)
 .def
      Data (SmartWare II)
 .def
      Defaults - definitions
 .def
      Linker definition file (TLink - WLink...)
 .dem
      Demo
 .dem
      Digital Elevation Model
 .dem
      Graphics (VistaPro)
 .der
      Internet security certificate
 .des
      Description
 .desc
      Description
 .dev
      Device driver
 .df
      Bitmap graphics (Hierarchical Data File) (NCSA)
 .dfd
      Data Flow Diagram graphic (Prosa)
 .dfd
      Dyadic functions (ABC programming language)
 .dfi
      Outline font description (Digifont)
 .dfl
      Default program settings (Signature)
 .dfm
      Data Flow Diagram model file (Prosa)
 .dfm
      Form file (Borland Delphi - C++ Builder)
 .dfs
      Delight Sound File
 .dfv
      Printing form (MS Word)
 .dfx
      Micrografx Effects DLL
 .dgn
      CAD drawing (vector) (MicroStation)
 .dgs
      Diagnostics
 .dh
      Dependency information for .ph (Geoworks)
 .dhp
      Bitmap graphics (Dr. Halo PIC)
 .dht
      Datafile (Gauss)
 .dia
      Diagraph graphics (Computer Support Corporation)
 .dib
      Bitmap graphics (Device Independent Bitmap)
 .dic
      Dictionary
 .dif
      Database (Data Interchange Format) (Visicalc)
 .dif
      Difference data file (Patch script)
 .dif
      Display Information File (OS/2)
 .diff
      Difference data file (Patch script)
 .dip
      Debug info processor (Watcom Debugger)
 .dir
      Dialing directory file (Procomm Plus)
 .dir
      Directory file (VAX - CPS Backup)
 .dir
      Movie format (MacroMind Director 4.x)
 .dis
      Distribution list (VAX Mail)
 .dis
      Thesaurus (CorelDraw)
 .diz
      Description file (Description In Zip)
 .dkb
      Raytraced graphics (DKBTrace)
 .dl
      Animation (Display - DL Viewer)
 .dld
      Data (Lotus 1-2-3)
 .dlg
      Dialog resource script file (MS Windows SDK)
 .dlg
      Dialog resources (DN)
 .dlg
      Digital Line Graph
 .dll
      Dynamic Link Library (Windows 3.x - OS/2)
 .dlm
      Data (FileMaker Pro)
 .dls
      Setup (Norton Disklock)
 .dmf
      Music format (Delusion Digital Music File) (Delusion)
 .dmo
      Demo (Derive)
 .dmp
      Dump file (eg. screen or memory)
 .dms
      Compressed Amiga file archive (DiskMasher)
 .doc
      Text document (binary file)
 .dog
      Screen file (Laughing Dog Screen Maker)
 .doh
      Dependency information for .poh (Geoworks)
 .dos
      DOS related file (Win95)
 .dos
      External command file (1st Reader)
 .dot
      Document template (MS Word)
 .dot
      Line-type definition file (CorelDraw)
 .dox
      Text document (MultiMate 4.0 - MS Word)
 .doz
      Description Out of Zip (VENDINFO)
 .dp
      Calendar file (Daily Planner)
 .dp
      Data file (DataPhile)
 .dp
      Primary data file (THOR database)
 .dpd
      Dyadic predicates (ABC programming language)
 .dpj
      Project (Borland Delphi)
 .dpr
      Default project- and state-related information (Borland C++ - Delphi)
 .dpx
      Bitmap graphics (Digital Moving Picture Exchange) (Cineon DPX file)
 .drs
      Display Resource (WordPerfect for Win)
 .drv
      Device driver (for hardware)
 .drw
      Vector graphics (Micrografx Designer format)
 .ds4
      Vector graphics (Micrografx Designer 4.x)
 .dsc
      Description file
 .dsc
      Discard file (Oracle)
 .dsd
      Database (DataShaper)
 .dsf
      Delusion Digital Sound File (Delusion)
 .dsk
      Disk Drivers (Novell NetWare)
 .dsk
      Project desktop (Borland C++)
 .dsm
      Digital sound module (DSI)
 .dsm
      Macro (MS Developer Studio)
 .dsn
      Design (Object System Designer)
 .dsn
      ODBC data source
 .dsp
      Display parameters (Signature)
 .dsp
      Dynamic Studio Professional Module (Dynamic Studio)
 .dsp
      Graphics display driver (Dr.Halo)
 .dsp
      Project (MS Developer Studio)
 .dsq
      Query file (Corel)
 .dsr
      Driver Resource (WordPerfect for Win)
 .dss
      Screensaver file (DCC)
 .dss
      Sound (Digital Soup)
 .dst
      WAIN (Scanner spec) data source DLL (Win)
 .dsw
      Project workspace (Borland C++ - MS Developer Studio)
 .dt_
      Data fork of a Macintosh file (Mac-ette)
 .dta
      Data file (Turbo Pascal - PC-File - Stata)
 .dtd
      Document Type Definition
 .dtf
      Database file (PFS - Q&A)
 .dtp
      Publication (PageMagic - Publish-It! - Publisher3)
 .dvc
      Data (Lotus 1-2-3)
 .dvi
      Text document (TeX Device Independent File Format) (TeX)
 .dvp
      Device parameter file (AutoCAD)
 .dvp
      Program information file (DESQview)
 .dw2
      Drawing (DesignCAD for windows)
 .dwb
      Workbench (Coryphaeus Software Designer)
 .dwc
      Compressed file archive (DWC)
 .dwd
      DiamondWare digitized sound
 .dwf
      Vector graphics (CAD programs)
 .dwg
      Drawing database (vector) (AutoCAD - Drafix) (CAD programs)
 .dx
      Cross-reference data (THOR database)
 .dx
      Document (Data explorer)
 .dx
      Text file (DEC WPS/DX format - DEC WPS Plus)
 .dxb
      Drawing binary exchange format (vector) (AutoCAD)
 .dxf
      Vector graphics (Drawing Exchange Format) (AutoCAD) (CAD programs)
 .dxn
      Fax (Fujitsu dexNET)
 .dy22
      Sound (Dyaxis format) (sampling rate 22k)
 .dy44
      Sound (Dyaxis format) (sampling rate 44k)
 .dyl
      Dynamic link library (EPOC16)
 .dyn
      Data (Lotus 1-2-3)


e

 .eas
       Extended file attributes (OS/2)
 .ebj
       Error-checking object file (Geoworks)
 .ebs
       Script source (Rational Rose 98)
 .ebx
       Compiled script (Rational Rose 98)
 .ec
       Preprosessed GOC source code file (error-checking version) (Geoworks)
 .ecg
       Preprosessed GOC source code file (error-checking version) (Geoworks)
 .edt
       Default settings (VAX EDT editor)
 .edt
       External editors definitions (DN)
 .eeb
       Equation editor button bar (WordPerfect for Win)
 .eer
       Execution error messages (Lahey Fortran)
 .efs
       Flowchart (EasyFlow)
 .eft
       High resolution screen font (ChiWriter)
 .efx
       Fax (Everex EFax)
 .ega
       EGA display font (Ventura Publisher)
 .eidi
       Bitmap graphics (Electric Image EIDI file)
 .eka
       Internal data files (Borland's Eureka)
 .el
       Elisp language source code file (Emacs lisp)
 .elc
       Compiled ELISP code (Emacs lisp)
 .eli
       Compressed file archive (ELI)
 .elt
       Event list (Prosa)
 .emf
       Vector graphics (Enhanced Metafile)
 .emu
       Terminal emulation data (BITCOM)
 .enc
       Encoded file - UUENCODEd file (Lotus 1-2-3 - uuencode)
 .enc
       Music (Encore)
 .end
       Arrow-head definition file (CorelDraw)
 .enff
       Extended Neutral File Format
 .eng
       Dictionary engine (Sprint)
 .eng
       Engine routines (Matlab)
 .eng
       English documentation
 .eng
       Graphics (charting) (EnerGraphics)
 .env
       Data (Novell Envoy)
 .env
       Enveloper macro (WOPR)
 .env
       Environment file (WordPerfect for Win)
 .eobj
       Object code (error-checking version) (Geoworks)
 .epd
       Publication (Express Publisher)
 .epi
       Encapsulated PostScript (text and graphics) (Express Publisher)
 .eps
       Encapsulated PostScript (text and graphics) (Adobe Illustrator)
 .eps
       Printer font (Epson - Xerox...) (Ventura Publisher)
 .epsf
       Encapsulated PostScript file (text and graphics)
 .epsi
       Encapsulated PostScript style preview file
 .epson
       Epson printer graphics file
 .eqf
       Equalizer Settings file (WinAmp)
 .eqn
       Equation (WordPerfect for Win)
 .er1
       Data (ERWin)
 .erd
       Entity Relationship Diagram graphic file (Prosa)
 .erm
       Bitmap graphics
 .erm
       Entity Relationship Diagram model file (Prosa)
 .err
       Error log
 .err
       Error messages for command line compilers
 .ers
       Satellite image header (ER Mapper file) (Earth Resource Mapping)
 .erx
       Data (ERWin)
 .esh
       Extended Shell batch file
 .eth
       Document (Ethnograph 3)
 .etx
       Structure Enhanced (setext) text
 .euc
       Japanese text (Kanji)
 .evp
       Sound envelope (general purpose data curves stored as doubles) (mxv)
 .evt
       Event descriptions
 .evt
       Event log
 .evy
       Document (WordPerfect Envoy)
 .ewd
       Document (Express Publisher for Windows)
 .ewl
       Document (Microsoft Encarta)
 .ex3
       Device driver (Harvard Graphics 3.0)
 .exc
       Exclude file for Optimize (do not process) (QEMM)
 .exc
       Rexx language source code file (VM/CMS)
 .exc
       Text document
 .exe
       Directly executable program (MSDOS)
 .exm
       Msdos executable system-manager compliant (HP calculator)
 .exp
       Express schema (STEP)
 .exp
       Protected mode executable program (PharLap)
 .ext
       Extension file (Norton Commander)
 .exx
       Intermediate file by MsgPut (IBM LinkWay)
 .ezf
       Fax (Calculus EZ-Fax)


f

 .f
      Compressed file archive (Freeze)
 .f
      Fortran language source code file (fixed form)
 .f01
      Fax (perfectfax)
 .f06
      Dos screen text font - height 6 pixels (fntcol13.zip)
 .f07
      Dos screen text font - height 7 pixels (fntcol13.zip)
 .f08
      Dos screen text font - height 8 pixels (fntcol13.zip)
 .f09
      Dos screen text font - height 9 pixels (fntcol13.zip)
 .f10
      Dos screen text font - height 10 pixels (fntcol13.zip)
 .f11
      Dos screen text font - height 11 pixels (fntcol13.zip)
 .f12
      Dos screen text font - height 12 pixels (fntcol13.zip)
 .f13
      Dos screen text font - height 13 pixels (fntcol13.zip)
 .f14
      Dos screen text font - height 14 pixels (fntcol13.zip)
 .f16
      Dos screen text font - height 16 pixels (fntcol13.zip)
 .f2r
      Music (Farandole Linear Module format)
 .f3r
      Music (Farandole blocked linear module format)
 .f77
      Fortran 77 language source code file
 .f90
      Fortran 90 language source code file (free form)
 .f96
      Fax (Frecom FAX96)
 .fac
      Bitmap graphics (UNIX Faceserver image file) (Usenix FACE)
 .face
      Bitmap graphics (UNIX Faceserver image file) (Usenix FACE)
 .fal
      Bitmap graphics (image header information) (Q0 format)
 .faq
      Frequently Asked Questions (text file)
 .far
      Music (Farandole Composer Module)
 .fas
      Compiled program (Macsyma)
 .fav
      Favorites shortcut (MS Outlook)
 .fax
      Fax (generic Group 3 1bit encoded data) (most Fax programs)
 .fbm
      Fuzzy Bitmap
 .fc
      Spell checking dictionary (Harvard Graphics 2.0)
 .fcm
      Binary file patch file (forward compression) (jlpak10.zip)
 .fd
      Declaration file (MS Fortran)
 .fd
      Field offsets for compiler (DataFlex)
 .fd
      Resource file (Front Door)
 .fdf
      Forms document (Adobe Acrobat)
 .fdw
      Form (F3 Design and Mapping)
 .feb
      Figure editor button bar (WordPerfect for Win)
 .fei
      Fatal Error Infotable (Geoworks)
 .ff
      Intelligont FIAS format
 .ff
      Outline font description (Agfa Compugraphics)
 .fff
      Fax (defFax)
 .ffi
      Atech FastFont (AllType)
 .ffivw
      File Format for the Interchange of Virtual Worlds
 .fft
      Fast Fourier Transform analysis data
 .fft
      Text file (DCA/FFT Final Form Text - DisplayWrite)
 .fh3
      Vector graphics (Aldus FreeHand 3.x)
 .fh4
      Vector graphics (Aldus FreeHand 4.x)
 .fi
      Interface file (MS Fortran)
 .fif
      Graphics (Fractal Image Format)
 .fig
      Linker options (Lahey Fortran)
 .fil
      File listing
 .fil
      File template (Application Generator)
 .fil
      Files list object file (dBASE Application Generator)
 .fil
      Overlay (WordPerfect)
 .fin
      Print-formatted text file (Perfect Writer - Scribble - MINCE)
 .fio
      Graphics filter (Aldus PhotoStyler)
 .fit
      File Index Table (Windows NT)
 .fit
      Graphics and data (Flexible Image Transport System)
 .fits
      Graphics and data (Flexible Image Transport System)
 .fix
      Patch file
 .fky
      Macro file (FoxPro)
 .fl
      Sound (Floating format) (hardware dependant not transportable)
 .flb
      Format library (Papyrus)
 .flc
      Animation (AutoDesk FLIC format) (Autodesk Animator)
 .fld
      Folder (Charisma)
 .fli
      Animation (AutoDesk FLIC format) (Autodesk Animator)
 .fli
      Tex font library (EmTeX)
 .flm
      Film Roll (AutoCAD/AutoShade)
 .flt
      Data filter file (Alsud - Micrografx Picture Publisher - MS Word)
 .flt
      Flight file (MultiGen)
 .flt
      Graphics filter (Asymetrix ToolBook - Corel)
 .flx
      Animation format
 .flx
      Compiled binary (DataFlex)
 .flx
      Database (Flexstor format)
 .fm
      Database (FileMaker Pro)
 .fm1
      Spreadsheet (Lotus 1-2-3 release 2.x)
 .fm3
      Device driver (Harvard Graphics 3.0)
 .fm3
      Spreadsheet (Lotus 1-2-3 release 3.x)
 .fmb
      File Manager Button bar (WordPerfect for Win)
 .fmf
      Font or icon file (IBM LinkWay)
 .fmk
      Makefile (Fortran PowerStation)
 .fmo
      Compiled format file (dBASE IV)
 .fmt
      Fast loading format (TeX)
 .fmt
      Format file (dBASE IV - FoxPro - Clipper 5 - dBFast - Gate3)
 .fmt
      Style sheet (Sprint)
 .fmv
      Full Motion Video file
 .fn3
      Font file (Harvard Graphics 3.0)
 .fnd
      Saved search (Windows 95)
 .fnt
      Font file (many)
 .fnx
      Inactive font (Exact)
 .fo1
      Font file (Borland Turbo C)
 .fo2
      Font file (Borland Turbo C)
 .fog
      Fontographer Database File (Fontographer3.5)
 .fol
      Folder of saved messages (1st Reader)
 .fon
      Bitmap font file (many - Windows 3.x font library)
 .fon
      Log of all calls (Procomm Plus)
 .fon
      Phonebook (Terminate - Terminator - Telix)
 .font
      Font data (unix)
 .fop
      Bitmap graphics (Freedom of Press)
 .for
      Form (WindowBase)
 .for
      Fortran language source code file (fixed form)
 .fot
      Truetype font styles file (installed font)
 .fox
      Foxbase executable (precompiled .prg) (FoxBase)
 .fp
      Configuration file (FoxPro)
 .fp
      Data (FileMaker Pro)
 .fp1
      Game data (Flying Pigs for Windows)
 .fp3
      Document (FileMaker Pro 3.0)
 .fpc
      Catalog (FoxPro)
 .fpd
      TMT Pascal compiled unit (TMT Pascal)
 .fpt
      Memo field tables (FoxPro)
 .fpw
      Floorplan drawing (FloorPLAN plus for Windows)
 .fpx
      Bitmap graphics (Kodak FlashPix)
 .fr3
      Renamed dBASE III+ form file (dBASE IV)
 .frf
      Font database file (FontMonger)
 .frg
      Uncompiled report file (dBASE IV)
 .frl
      Library (GP-Forth)
 .frm
      Form ie. dialog layout (Visual Basic)
 .frm
      Formula (Fractint)
 .frm
      Merge form (WordPerfect)
 .frm
      Order or registration form (text file)
 .frm
      Report file (dBASE IV - Clipper 5 - dBFast)
 .fro
      Compiled report file (dBASE IV)
 .frp
      Form (PerForm PRO Plus - FormFlow)
 .frs
      Screen Font Resource (WordPerfect for Win)
 .frt
      Additional (FPT) report description file (FoxPro)
 .frt
      GP-Forth language source code file (GP-Forth)
 .frx
      Form stash file (binary) (Visual Basic)
 .frx
      Main (DBF) report description file (FoxPro)
 .frz
      Freeze file (EPOC)
 .fs
      Bitmap graphics (Usenix FaceServer file)
 .fsl
      Form (Paradox for Windows)
 .fsm
      Music format (Farandole Composer WaveSample)
 .fssd
      Sound
 .fst
      Linkable program (dBFast)
 .fsx
      Data (Lotus 1-2-3)
 .ftm
      Font file (Micrografx)
 .ftn
      Fortran language source code file (fixed form)
 .ftp
      Configuration (FTP Software PC/TCP)
 .ftp
      Document (FTP Voyager)
 .fts
      Full text search (Windows 95)
 .fts
      Graphics (Flex Image Transport)
 .fw
      Database (FrameWork)
 .fw2
      Database (Framework II)
 .fw3
      Database (Framework III)
 .fweb
      Fortran WEB
 .fx
      On-line guide (FastLynx)
 .fxd
      Phonebook (FAXit)
 .fxp
      Executable precompiled .prg (FoxPro)
 .fxs
      Fax Transmit Format graphics (WinFax)
 .fzp
      Dye Sub printing support file (Fargo Primera colour printer)


g

 .g
       Data chart (APPLAUSE)
 .g16
       Compiled config (GoldED for DOS)
 .g3
       Bitmap graphics (Group 3 FAX file)
 .g8
       Green channel image data (24bit 3D animation) (Cubicomp PictureMaker)
 .g8
       Raw graphics (one byte per pixel) plane three (PicLab)
 .gal
       Gallery (Corel Multimedia Manager)
 .gam
       Fax (GammaFax)
 .gb
       Chinese text
 .gb
       Gameboy game
 .gbl
       Global definitions (VAXTPU editor)
 .gbl
       Global module in Basic programs
 .gc1
       Lisp language source code file (Golden Common Lisp 1.1)
 .gc3
       Lisp language source code file (Golden Common Lisp 3.1)
 .gcd
       Generic CAD Drawing format (vector)
 .gdf
       Dictionary file (GEOS)
 .gds
       McDonnell-Douglas Things
 .ge
       Config file (GEcho)
 .ged
       Compiled config file (GoldED for DOS)
 .ged
       Graphics (Graphic Environment Document) (Arts & Letters)
 .ged
       Graphics editor file (EnerGraphics)
 .gef
       Graphics Exchange Format
 .gem
       Vector graphics (Digital Research GEM metafile) (Ventura Publisher)
 .gen
       Compiled template (dBASE Application Generator)
 .gen
       Generated text file (Ventura Publisher)
 .geo
       Compiled config file (GoldED for OS/2)
 .geo
       Geode (GEOS executable) (Geoworks)
 .gex
       Config file (GEcho)
 .gf
       Font file (MetaFont)
 .gfb
       Compressed GIF image (GIFBlast)
 .gfi
       Genigraphics Graphics Link presentation
 .gfo
       SGI Radiosity
 .gft
       Font file (GEM - NeoPaint)
 .gfx
       Genigraphics Graphics Link presentation
 .gfx
       Graphics Files (Instant Artist)
 .gib
       Chart (Graph-in-the-Box)
 .gid
       General index (Windows 95 help)
 .gif
       Bitmap graphics (GIF87A/GIF89A CompuServe Graphics Interchange Format)
 .giff
       Bitmap graphics (GIF87A/GIF89A CompuServe Graphics Interchange Format)
 .gim
       Genigraphics Graphics Link presentation
 .gis
       Bitmap graphics (Erdas gray-scale image)
 .giw
       Presentation (Graph-in-the-Box for Windows)
 .gix
       Genigraphics Graphics Link presentation
 .gkh
       Disk Image (VFX SD EPS ASR TS) (Ensoniq)
 .gks
       Graphics Kernel System
 .gl
       Animation (GRASP - GRAphical System for Presentation format)
 .gl
       Script (GALink)
 .glb
       Global module in Basic programs
 .glm
       Datafile (Glim)
 .glo
       Auxiliary for for glossary (LaTeX)
 .glo
       Global module in Basic programs
 .gls
       Datafile (Across)
 .gly
       Glossary (MS Word)
 .gm
       Bitmap graphics (Autologic files)
 .gm2
       Bitmap graphics (mode 2 black/white) (Autologic files)
 .gm4
       Bitmap graphics (mode 4 gray-scale) (Autologic files)
 .gmf
       CGM graphics (APPLAUSE)
 .gmp
       Geomorph tile map (SPX)
 .gna
       Genigraphics Graphics Link presentation
 .gnt
       Generated code (Micro Focus COBOL/2)
 .gnx
       Genigraphics Graphics Link presentation
 .go
       Bitmap graphics (GraphOn graphics file)
 .gobj
       Object code (non-error-checking version) (Geoworks)
 .goc
       GOC language source code file (Geoworks)
 .goe
       Satellite image data (GOES file) (McIDAS system)
 .goes
       Satellite image data (GOES file) (McIDAS system)
 .goh
       Goc language header file (Geoworks)
 .gould
       Bitmap graphics (Gould scanner file)
 .gp
       Geode parameter file (Geoworks)
 .gp
       Gofer project (Haskell language dialect)
 .gp4
       GTX Group IV format
 .gph
       Graph (Lotus 1-2-3/G)
 .gpk
       Compressed Omnigo file archive (Geos package)
 .gq
       Epson's page description language (printer)
 .gr2
       Screen driver (Windows 3.x)
 .gra
       Chart (MS Graph 97)
 .gra
       Datafile (SigmaPlot)
 .gra
       Graph (Microsoft Graph)
 .grads
       Metafile
 .grasp
       Animation (GRAphical System for Presentation format)
 .gray
       Bitmap graphics (raw gray bytes)
 .grb
       Bitmap graphics B&W binary (GROB Graphic Object) (HP-48sx calculator)
 .grb
       Ms-DOS Shell Monitor file (MS-DOS 5)
 .grd
       Drivers for GRX (graphics library)
 .grdef
       UI resource file (Geoworks)
 .grf
       Graph file (Graph Plus - Charisma)
 .grib
       Gridded Binary (FM 92-VIII Ext. GRIdded Binary file) (WMO CBS)
 .grn
       Drivers for GRX (graphics library)
 .grp
       Group file (Windows 3.x - Papyrus)
 .grp
       Pictures group (PixBase)
 .gry
       Graphics (Raw GREY)
 .gs
       Gofer script (Haskell language dialect)
 .gs1
       Presentation (GraphShow)
 .gsd
       GSM internet realtime audio
 .gsd
       Vector graphics (Professional Draw)
 .gsm
       Sound (GSM 6.10 prI-ETS 300 036 13kbit/s) (Internet phones)
 .gsp
       Sketch (Geometer's Sketchpad)
 .gss
       Script (Geometer's Sketchpad)
 .gsw
       Worksheet (GraphShow)
 .gtar
       Compressed file archive (GNU tar)
 .gtx
       Raster graphics (GTX Group IV)
 .gup
       Data (PopMail)
 .gv
       GrandView outline file
 .gwx
       Genigraphics Graphics Link presentation
 .gwz
       Genigraphics Graphics Link presentation
 .gxl
       Graphics library (Genus)
 .gym
       Generic symbol file (Geoworks)
 .gz
       Compressed file archive (GNU Zip)
 .gzip
       Compressed file archive (GNU Zip)


h

 .h
       Header file
 .h!
       Help database (Flambeaux Help - Perfect Database)
 .h++
       Header file (C++)
 .h--
       Header file (Sphinx C--)
 .ha
       Compressed file archive (HA)
 .hal
       Data file (Hyper Access Lite OS/2)
 .ham
       Disk Drivers NPA (Novell NetWare)
 .hap
       Compressed file archive (HAP)
 .hbk
       Handbook (Mathcad)
 .hbm
       Hotline bookmark
 .hc
       Header file
 .hcom
       Sound (Macintosh)
 .hdf
       Bitmap graphics (Hierarchical Data File) (NCSA)
 .hdf
       Help file (Help Development Kit)
 .hdl
       Alternate download file listing (Procomm Plus)
 .hdr
       Database header (Pc-File+)
 .hdr
       Datafile (Egret)
 .hdr
       Message header (Procomm Plus - 1st Reader)
 .hds
       Hierarchical Data System
 .hdw
       Vector graphics (Harvard Draw)
 .hdx
       Help index (AutoCAD - Zortech C++)
 .hed
       Document (HighEdit)
 .hel
       Game data (Microsoft Hellbender)
 .hep
       Novell Help Librarian Data File (Novell NetWare)
 .hex
       Encoded file archive (ascii) (Macintosh BinHex)
 .hex
       Hex dump
 .hfi
       Hp Font Info file (GEM)
 .hgl
       Highlight groups definitions (DN)
 .hgl
       Vector graphics (HP Graphics Language)
 .hh
       C++ header file
 .hhh
       Precompiled header file (Power C)
 .hhp
       Help information for remote users (Procomm Plus)
 .hi
       High scores (games)
 .hig
       High scores (games)
 .hin
       Molecule (HyperChem)
 .hips
       Bitmap graphics (HIPS file)
 .his
       History of executing/viewing/editing (DN)
 .hlb
       Help library (VMS)
 .hlp
       Program online help information
 .hlx
       Help file (MultiEdit)
 .hlz
       Packed help file (MultiEdit)
 .hmi
       Music (MIDI)
 .hmm
       Alternate Mail Read option menu (Procomm Plus)
 .hmp
       Music (MIDI)
 .hnc
       CNC program files Heidenhain (?) dialog
 .hof
       Game data (best scores)
 .hp
       Primary hash file (THOR database)
 .hp
       Printout file for HP printers/plotters (HP/GL)
 .hp8
       Text in HP Roman8 character set (NewWave Write)
 .hpf
       HP LaserJet fonts (PageMaker)
 .hpg
       Vector graphics (HPGL plotter file) (AutoCad - Harvard Graphics)
 .hpgl
       Vector graphics (plotter file) (Hewlett-Packard Graphics Language)
 .hpi
       Font information (GEM)
 .hpj
       Help project (MS Help Compiler)
 .hpj
       Printed to file (HP LaserJet)
 .hpk
       Compressed file archive (HPack)
 .hpl
       Vector graphics (Hewlett-Packerd LasetJet)
 .hplj
       Vector graphics (Hewlett-Packerd LasetJet)
 .hpm
       Alternate Main menu for privileged users (Procomm Plus)
 .hpm
       Emm text (HP NewWave)
 .hpm
       High Performance Map (Quaestor 1.x)
 .hpp
       C++ header (Zortech C++ - Watcom C/C++)
 .hpp
       Vector graphics (Hewlett-Packard Printer Control Language)
 .hppcl
       Vector graphics (Hewlett-Packard Printer Control Language)
 .hqx
       Encoded Macintosh archive (ascii) (BinHex)
 .hrf
       Bitmap graphics (Hitachi Raster Format) (CADCore)
 .hrh
       Common header for resources and C++
 .hrm
       Alternate Main menu for limited/normal users (Procomm Plus)
 .hrz
       Graphics (SSTV)
 .hs
       Literate Haskell source code file
 .hs2
       Monochrome image (Postering)
 .hsc
       2-op FM music file (HSC tracker)
 .hsi
       Bitmap graphics (Handmade Software Inc) (Image Alchemy)
 .hsp
       WWW page project (HomeSite)
 .hst
       Graphics histogram (HSI raw file) (Handmade Software)
 .hst
       History
 .ht
       Data (HyperTerminal)
 .htm
       HyperText Markup Language document (WWW)
 .html
       HyperText Markup Language document (WWW)
 .htmls
       HyperText Markup Language document with server-side include (WWW)
 .htt
       HyperText Template
 .htx
       HTML template (MS FrontPage)
 .hwd
       Presentation (Hollywood)
 .hx
       Cross-reference hash file (THOR database)
 .hxm
       Alternate Protocol Selection menu for all users (Procomm Plus)
 .hxx
       C++ header
 .hy1
       Hyphenation algorithms (Ventura Publisher)
 .hy2
       Hyphenation algorithms (Ventura Publisher)
 .hyc
       Data (WordPerfect)
 .hyd
       Hyphenation dictionary (WordPerfect for Win)
 .hyp
       Compressed file archive (Hyper)
 .hz
       Chinese text


i

 .i
        Analysis data (Phase Vocorder)
 .i
        Preprocessor output file (Borland C Preprocessor)
 .i3
        Interface source (Modula-3)
 .iax
        Bitmap graphics (IBM Image Access eXecutive file)
 .ibg
        Planetary images by NASA (PDS format)
 .ibm
        Compressed file archive (Internal IBM only) (ARCHDOS)
 .ic
        M3CG intermediate language file (Modula-3)
 .ic1
        Bitmap graphics (Atari Image)
 .ic2
        Bitmap graphics (Atari Image)
 .ic3
        Bitmap graphics (Atari Image)
 .ica
        Bitmap graphics (Image Object Content Architecture)
 .ica
        Citrix file
 .ica
        Icon archive (IoCA)
 .icb
        Bitmap graphics (Targa bitmap)
 .icc
        Bitmap graphics (Kodak ICC printer file)
 .ice
        Archive (Cracked LHA) (old Lha)
 .icm
        ICC configuration
 .icn
        Graphics (RIP icon)
 .icn
        Icon language source code file
 .ico
        Icon image (Windows 3.x)
 .icon
        Icon image (1bit) (Sun icon file) (Unix)
 .icp
        Parameter file (IContact) (Unix)
 .icr
        Bitmap graphics (NCSA Telnet Interactive Color Raster graphic file)
 .id
        Disk identification file
 .idb
        Database (IDA)
 .idc
        Bitmap graphics (Core Software Tech CORE IDC file)
 .idc
        Document (Internet Database Connector)
 .idc
        IDA C language source code file (IDA)
 .idd
        MIDI Instrument Definition
 .ide
        Project (Borland C++ 4.x)
 .idf
        MIDI instrument definition
 .idl
        Interface definition file (Visual C++)
 .ids
        Imported names format (IDA)
 .idw
        Vector graphics (IntelliDraw)
 .idx
        Header information (CMYK image) (Stork format)
 .idx
        Index (many - FoxPro)
 .ief
        Bitmap graphics (Image Exchange Format)
 .ifd
        Form (JetForm Design)
 .iff
        Bitmap graphics (Sun TAAC Image File Format)
 .iff
        Bitmap graphics or sound (Amiga IFF/8SVX Interchange File Format)
 .ifp
        Script (KnowledgeMan)
 .ifs
        Fractal image compressed file (YuvPak)
 .ifs
        Installable file system (OS/2)
 .ifs
        Iterated function system fractal (Fractint)
 .ig
        Generic interface source (Modula-3)
 .iges
        2D or 3D CAD model (Initial Graphics Exchange Specification format)
 .igf
        Inset Systems metafile
 .igs
        2D or 3D CAD model (Initial Graphics Exchange Specification format)
 .ihp
        Help file (Watcom)
 .ihs
        Inbound History (Bink/+)
 .ii
        Preprocessed C++ source code (gcc)
 .iif
        Interchange file (QuickBooks for Windows)
 .il
        Inline expansion file (Fortran 90)
 .il
        hDC Designer Icon Lin Dll format
 .ilb
        Data (Scream Tracker)
 .ilbm
        Bitmap graphics (Amiga Interleaved Bitmap format)
 .ilk
        Outline of program's format (incremental linker) (MS ILink)
 .im
        Bitmap graphics (Sun raster file)
 .im1
        Bitmap graphics (1bit) (Sun raster file)
 .im24
        Bitmap graphics (24bit) (Sun raster file)
 .im32
        Bitmap graphics (32bit) (Sun raster file)
 .im8
        Bitmap graphics (8bit) (Sun raster file)
 .ima
        Graphics (WinImage)
 .ima
        Mirage vector graphics (EGO - Chart - Autumn)
 .image
        Disk Image (Disk Copy, ShrinkWrap)
 .img
        Bitmap graphics (GEM or ADEX format) (Ventura Publisher)
 .img
        Disk Image (Disk Copy, ShrinkWrap)
 .imp
        Compressed file archive (IMP)
 .imp
        Pascal implementation
 .imp
        Spreadsheet (Lotus Improv)
 .imq
        Image presentation (ImageQ)
 .imq
        Planetary images by NASA (PDS format)
 .in
        Input
 .in$
        Installation file (HP NewWave)
 .in3
        Input device driver (Harvard Graphics 3.0)
 .inb
        Test script (Vermont HighTest)
 .inc
        Include file (several programming languages)
 .ind
        Data Index (dBASE IV)
 .inf
        Hypertext help system file (OS/2)
 .inf
        Information (ascii file)
 .inf
        Setup information
 .info
        GNU info reader (output from texinfo) (unix)
 .info
        Icon Data (Amiga)
 .ingr
        Intergraph Raster File Format
 .ini
        Initialization file
 .ink
        Pantone reference fills file (CorelDraw)
 .inl
        C++ inline function implementation
 .inn
        Overlay (Micro Focus COBOL/2)
 .ins
        Datafile (WordPerfect)
 .ins
        Installation script (1st Reader)
 .ins
        Instrument File (Adlib - Ensoniq)
 .ins
        Internet communications settings (MS IIS)
 .int
        Interface module source (Borland)
 .int
        Intermediate code (semi-compiled) (Signature - Micro Focus COBOL/2)
 .inx
        Index (Foxbase)
 .io
        Compressed file archive (CPIO)
 .io
        Object file (Modula-3)
 .iob
        3d graphics database in TDDD format
 .ioc
        Organizational chart (Instant ORGcharting!)
 .ion
        Descript.ion file (file descriptions) (4DOS)
 .ip
        Data (Interactive Physics)
 .ip
        Inspection Procedures (NRC Inspection Manual)
 .ipl
        Pantone Spot reference palette file (CorelDraw)
 .ips
        IPScript (IPIX)
 .ipx
        IPIX file (IPIX)
 .iqy
        Web query file (MS Excel)
 .irc
        Sound (IRCAM format)
 .iris
        Bitmap graphics (Silicon Graphics RGB image file)
 .irs
        Resource (WordPerfect)
 .irtp
        Graphics (Graphicon-2000 Interactive Real-Time PHIGS)
 .is
        Intermediate assembly file (Modula-3)
 .isd
        Spelling Checker dictionary (RapidFile)
 .ish
        Compressed file archive (ISH)
 .iso
        ISO-9660 table
 .isp
        Internet service provider settings (MS IIS)
 .it
        Music (Impulse Tracker)
 .it
        Settings (intalk)
 .itf
        Interface file (JPI TopSpeed Pascal)
 .its
        Internet Document Set
 .iv
        3D object (Open Inventor format)
 .iv-vrml
        Inventor VRML Format document
 .ivb
        Bitmap graphics (Truevision Targa format)
 .ivr
        Virtual reality world (live picture)
 .ivt
        Information title (InfoViewer)
 .iw
        Presentation flowchart (IconAuthor - HSC InterActive)
 .iw
        Screensaver (Idlewild)
 .iwa
        Text document (IBM Writing Assistant)
 .iwp
        Text document (Wang)
 .ix
        Linker information (Modula-3)
 .izt
        Binary token file (IZL)


j

 .j
      Compressed file archive (JAR)
 .jam
      Jam messagebase (FTN software)
 .jam
      Music (JamTracker module)
 .jar
      Compressed file archive (Java archive) (JAR)
 .jas
      Bitmap graphics (JAS Compressed)
 .jasc
      Graphics (JAS Compressed)
 .jav
      Java language source code file
 .java
      Java language source code file
 .jbd
      Datafile (SigmaScan)
 .jbf
      Jasc Browser File
 .jbig
      Bitmap graphics (1-bit raster image) (Joint Bilevel Image Group)
 .jbx
      Project file (Project Scheduler 4)
 .jcm
      Java commerce message
 .jet
      Fax (Hybrid JetFax)
 .jff
      Bitmap graphics (JPEG File Interchange Format)
 .jfi
      Bitmap graphics (JPEG File Interchange Format)
 .jfif
      Bitmap graphics (JPEG File Interchange Format)
 .jif
      Bitmap graphics (JPEG File Interchange Format)
 .jis
      Japanese Industry Standard (text)
 .jms
      Music format (JMusic file) (UltraForce)
 .jn1
      Game data (Epic MegaGames Jill of the Jungle)
 .job
      Job object (Scheduler)
 .joi
      Join conferences file (XBoard)
 .jor
      Journal file (Gupta SQLWindows)
 .jou
      Journal file (VAX Edt editor)
 .jpc
      Bitmap graphics (Japan Picture format)
 .jpe
      Bitmap graphics (JPEG Joint Photography Experts Group format)
 .jpeg
      Bitmap graphics (JPEG Joint Photography Experts Group format)
 .jpg
      Bitmap graphics (JPEG Joint Photography Experts Group format)
 .jrc
      Compressed file archive (JRchive)
 .js
      JavaScript language source code file (script)
 .jsm
      Jigsaw file (JugWin)
 .jss
      Jigsaw file (JugWin)
 .jtf
      Bitmap graphics (JPEG Tagged Interchange Format)
 .jtf
      Fax (Hayes JT Fax)
 .jut
      Jutvision Scene (Jutvision)
 .jw
      Text document (JustWrite)
 .jwl
      Library (JustWrite)
 .jzz
      Spreadsheet (Jazz)


k

 .k3d
      Description of macro language (3DS)
 .kar
      Karaoke (MIDI music with word track)
 .kar
      Precompiled .prg for KARAT (Rus. FOX+ 2.0)
 .kb
      Keyboard script (Borland C++ 4.5)
 .kb
      Program source (Knowledge Pro)
 .kbd
      Keyboard mapping (LocoScript - Signature - Procomm Plus)
 .kbm
      Keyboard mapping (Reflection 4.0)
 .kcl
      Lisp language source code file (Kyoto Common Lisp)
 .kdc
      Bitmap graphics (Kodak Digital Camera) (PhotoEnhancer)
 .kdk
      Bitmap graphics (Kodak proprietary decimated TIFF format)
 .kex
      Macro (KEDIT)
 .key
      Archive .key-file (OS/2)
 .key
      Datafile (Forecast Pro)
 .key
      Keyboard macros
 .key
      Security file eg. Registration info
 .kfx
      Graphics (Group 4 image) (KoFax)
 .kit
      Power Chords drum kit file (Power Chord)
 .kml
      Kedit Macro Library
 .knn
      Database key file (Clarion)
 .kpp
      Toolpad (SmartPad)
 .kps
      Ibm KIPS bitmap graphics
 .kqp
      Bitmap graphics (Konica Quality Photos)
 .krz
      Kurzweil K2000 File (Kurzweil)
 .kyb
      Keyboard mapping (FTP Software PC/TCP)
 .kye
      Game data (Kye)


l

 .l
        L-System fractal (Fractint)
 .l
        Lex language source code file
 .l
        Linker directive file (WATCOM wlink)
 .l
        Lisp language source code file
 .la
        Netscape packetized audio (LiveAudio)
 .lab
        Datafile (NCSS - SOLO)
 .lab
        Mailing labels (Q+E for MS Excel)
 .lam
        Streaming audio metafile (Netscape Media Player)
 .lan
        Bitmap graphics (Erdas true colour image)
 .lan
        LAN Drivers (Novell NetWare)
 .landsat
        Bitmap graphics (EOSAT's Landsat Thematic Mapper data file)
 .latex
        Text document (LaTeX)
 .lay
        Word chart layout (APPLAUSE)
 .lbg
        Label generator data (dBASE IV)
 .lbl
        Label (dBASE IV - Clipper 5 - dBFast)
 .lbm
        Bitmap graphics (Amiga Interleaved Bitmap format) (Deluxe Paint)
 .lbm
        Linear bitmap graphics (XLib)
 .lbo
        Compiled label (dBASE IV)
 .lbr
        Compressed file archive (LU)
 .lbr
        Display driver (Lotus 1-2-3)
 .lbt
        Additional (FPT) label description file (FoxPro)
 .lbx
        Main (DBF) label description file (FoxPro)
 .lcf
        Linker Control File (Norton Guides compiler)
 .lch
        Chart (IBM Works for OS/2)
 .lck
        Lock file (especially for database access control)
 .lcl
        Data (FTP Software PC/TCP)
 .lcn
        Lection (WordPerfect)
 .lcs
        Datafile (ACT! History Files)
 .lcw
        Spreadsheet (Lucid 3-D)
 .ld
        Long Distance codes file (Telix)
 .ld1
        Overlay file (dBASE)
 .ldb
        Data filer database (IBM Works for OS/2)
 .ldb
        Record-locking information (MS Access)
 .ldf
        Data filer form (IBM Works for OS/2)
 .ldf
        Library definition file (Geoworks)
 .le
        Executable image (DOS/4GW PM 32X DOS Extender)
 .leg
        Document (Legacy)
 .les
        Lesson (check *.cbt)
 .lev
        Level file (eg. NetHack 3.x)
 .lex
        Lexicon (dictionary) (many)
 .lfd
        LucasArts resource file (LucasArts games)
 .lft
        Laser printer font (ChiWriter)
 .lg
        Compressed file archive (Arhangel)
 .lg
        Logo procedure definitions (LSRHS Logo)
 .lgo
        Logo for header and footer (SuperFax)
 .lgo
        Startup logo code (Windows 3.x)
 .lha
        Compressed file archive (LHA - LHARC)
 .lhs
        Literate Haskell source code file
 .lhw
        Compressed Amiga file archive (LHWarp)
 .lhz
        Compressed file archive (LHA)
 .lib
        Library file (several programming languages)
 .lic
        License file
 .lif
        Compressed file archive (CA Clipper installer)
 .lif
        Logical Interchange Format data file (Hewlett-Packard)
 .lim
        Compressed file archive (Limit)
 .lin
        Line types (AutoCAD)
 .lin
        Vector data (ARC format)
 .lis
        Listing (VAX)
 .lispm
        Bitmap graphics (Lisp Machine file)
 .lj
        Bitmap graphics (HP LaserJet graphics file)
 .lku
        T9000 linkable unit
 .ll3
        Laplink III related file (document) (LapLink III)
 .lma
        Netscape packetized audio (LiveAudio)
 .lmp
        Demo for Doom (3D computer game) (Doom - Doom2)
 .ln03
        Bitmap graphics (DEC LN03+ Sixel file)
 .lng
        Language definition file
 .lng
        Language extensions (Lahey Fortran)
 .lnk
        Link (shortcut) (Windows 95)
 .lnk
        Linker script (.RTLink)
 .loc
        Localisation string resource header file
 .lod
        Load file
 .lof
        Auxiliary file for List Of Figures (LaTeX)
 .log
        Log file
 .lot
        Auxiliary file for List Of Tables (LaTeX)
 .lpc
        Printer driver (TEKO)
 .lpc
        Sound (Linear Predictive Coding)
 .lpd
        Nuts and Bolts file (Helix)
 .lrc
        Intel Video Phone file
 .lrf
        Linker response file (MS C/C++)
 .lrp
        Report (IBM Works for OS/2)
 .lrs
        Language Resource File (WordPerfect for Win)
 .lrt
        Log file (Yacc)
 .lsa
        Ascii data (LightScape Technologies)
 .lsb
        Binary data (LightScape Technologies)
 .lsp
        Lisp language source code file (AutoLISP - Xlisp)
 .lss
        Spreadsheet (Legato - IBM Works for OS/2)
 .lst
        Keyboard macro (1st Reader)
 .lst
        List file (archive index - compiler listfile)
 .lst
        Listing (e.g. source code)
 .lst
        Spool file (Oracle)
 .ltm
        Bitmap graphics (EOSAT's Landsat Thematic Mapper data file)
 .ltm
        Form (Lotus Forms)
 .ltx
        Mathematical text document (LaTeX)
 .lwd
        Text document (LotusWorks)
 .lwob
        Lightwave Object Format
 .lwp
        Document (Lotus Word Pro)
 .lwp
        Word processor (IBM Works for OS/2)
 .lyr
        Song lyrics (ascii)
 .lzd
        Difference file for binaries (Ldiff 1.20)
 .lzh
        Compressed file archive (LHA - LHARC)
 .lzs
        Compressed file archive (LARC)
 .lzw
        Compressed Amiga file archive (LHWarp)


m

 .m
         Common binary file name extension (Maple)
 .m
         Function and commands (Matlab M-file - Mathematica)
 .m
         Macro module (Brief)
 .m
         Objective-C language source code file (gcc)
 .m
         Script file (Miranda programming language)
 .m
         Standard package (Mathematica)
 .m11
         Sound (Farallon's MacRecorder format) (sampling rate 11k)
 .m11
         Text file (MASS11)
 .m1a
         MPEG-1 audiostream
 .m1s
         MPEG-1 systemstream
 .m1v
         MPEG-1 IPB videostream
 .m2
         Modula 2 language source code file
 .m22
         Sound (Farallon's MacRecorder format) (sampling rate 22k)
 .m2a
         Sound (MPEG-2 audio)
 .m2v
         Video (MPEG-2 IPB videostream)
 .m3
         Modula3 language source code file
 .m3a
         Sound (MPEG-3 audio)
 .m3d
         3d animation macro (Corel Motion)
 .m3u
         Sound reference (MPEG URL)
 .m4
         M4 preprocessor file (unix)
 .m7
         Sound (Farallon's MacRecorder format) (sampling rate 7k)
 .m_u
         Backup of boot sector FAT and boot dir (MazeGold)
 .ma
         Ascii file (notebook) (Mathematica)
 .ma
         hDC products for MicroApp executable files (MicroApp)
 .ma3
         Macro (Harvard Graphics 3.0)
 .mac
         Bitmap graphics B&W (Apple Macintosh MacPaint file)
 .mac
         Macro
 .macp
         Bitmap graphics B&W (Apple Macintosh MacPaint file)
 .mad
         Module shortcut (MS Access)
 .maf
         Form shortcut (MS Access)
 .mag
         Woody Lynn's MAG graphics format (MPS Magro Paint System)
 .mah
         Settings (Mahjongg Solitaire)
 .mai
         Mail message (VAX)
 .mak
         Project makefile
 .mam
         Macro shortcut (MS Access)
 .man
         Formatted manual page
 .map
         Color palette (colormap intensities and indices)
 .map
         Format data (Micrografx Picture Publisher)
 .map
         Geographical map (Atlas MapMaker)
 .map
         Linker map file
 .map
         Network map (AccView)
 .maq
         Query shortcut (MS Access)
 .mar
         Assembly program (VAX Macro)
 .mar
         Report shortcut (MS Access)
 .marm
         Makefile for MARM platform (EPOC)
 .mas
         Smartmaster set (Freelance Graphics)
 .mat
         Matrix data file (Matlab)
 .mat
         Table shortcut (MS Access)
 .max
         Max language source code file
 .max
         Scene (3D Stdio Max)
 .maz
         Data (dVS/dVISE)
 .maz
         Game data (Hover maze)
 .mb
         Binary file (bitmaps etc.) (Mathematica)
 .mb
         Memo field values for database (Paradox)
 .mb1
         Game data (Apogee Monster Bash)
 .mbfavs
         Bitmap graphics (24bit) (AVS X image file)
 .mbfavs
         Bitmap graphics (AVS X image file)
 .mbfx
         Bitmap graphics (24bit) (AVS X image file)
 .mbfx
         Bitmap graphics (AVS X image file)
 .mbk
         Multiple index file backup (dBASE IV)
 .mbm
         Multi-bitmap file (EPOC)
 .mbx
         Mailbox (Eudora/Zerberus)
 .mc
         M3CG intermediate language file (Modula-3)
 .mc
         Manual Chapter (NRC Inspection Manual)
 .mc$
         Magic Xchange package (Magic Cap file archive)
 .mcc
         Configuration file (Mathcad)
 .mcc
         Dialer10 calling card
 .mcc
         Shortcut to MSN (Windows 95)
 .mcd
         Document (Mathcad)
 .mcf
         Font file (Mathcad)
 .mcf
         Graphics (Hotsauce)
 .mci
         Command script (Media Control Interface)
 .mcl
         Macro library (MultiEdit)
 .mcp
         Application script (Capsule)
 .mcp
         Composed Media multimedia file (NetMC Player)
 .mcp
         Printer driver (Mathcad)
 .mcs
         Image (MathCAD)
 .mcw
         Text document (MacWrite II - MS Word for Macintosh)
 .md
         Compressed file archive (MDCD)
 .mda
         Add-in (MS Access)
 .mdb
         Database (MS Access)
 .mde
         MDE database (MS Access)
 .mdl
         Geometrical model (3D Design Plus)
 .mdl
         Object design model (Rational Rose 98)
 .mdl
         Spreadsheet (CA-Compete!)
 .mdm
         Modem definition (TELIX)
 .mdn
         Blank database template (MS Access)
 .mdp
         Project workspace (MS Developer Studio)
 .mdr
         Microdrive file (ZX Spectrum emulator)
 .mdt
         Add-in data (MS Access)
 .mdt
         Data table (MS ILink incremental linker)
 .mdw
         Workgroup information (MS Access)
 .mdx
         Multiple index file (dBASE IV)
 .mdz
         Database wizard (MS Access)
 .mdz
         Description of music module (Cubic Player - Cross-View)
 .me
         Ascii text (READ.ME)
 .me
         Configuration (MultiEdit)
 .me
         Formatted manual page with me macros
 .meb
         Macro Editor bottom overflow file (WordPerfect Library)
 .mec
         MECCA source (Maximus)
 .med
         Macro Editor delete save (WordPerfect Library)
 .med
         Music format (Amiga MED/OctaMED)
 .mem
         Macro Editor macro (WordPerfect Library)
 .mem
         Memory variable save file (Clipper - dBASE IV - FoxPro)
 .mem
         Memos datafile (Clarion)
 .meq
         Macro Editor print queue file (WordPerfect Library)
 .mer
         Macro Editor resident area (WordPerfect Library)
 .mes
         Macro Editor work space file (WordPerfect Library)
 .mes
         Message
 .met
         Document (Omnipage Pro)
 .met
         Graphics metafile (OS/2)
 .met
         Macro Editor top overflow file (WordPerfect Library)
 .met
         Metafile (OS/2)
 .meu
         Menu group (DOS Shell)
 .mex
         Dynamically linked subroutines (Macintosh) (Matlab)
 .mex
         Macro Editor expound file (WordPerfect Library)
 .mex4
         Dynamically linked subroutines (Sun-4/SPARC) (Matlab)
 .mexds
         Dynamically linked subroutines (DECStation) (Matlab)
 .mexhp3
         Dynamically linked subroutines (HP9000/series 300) (Matlab)
 .mexhp7
         Dynamically linked subroutines (HP9000/series 700) (Matlab)
 .mexn
         Dynamically linked subroutines (NeXT) (Matlab)
 .mexrs6
         Dynamically linked subroutines (IBM RS/6000) (Matlab)
 .mexsg
         Dynamically linked subroutines (SGI) (Matlab)
 .mf
         Metafont text file (TeX)
 .mfd
         Monadic functions (ABC programming language)
 .mfj
         MetaFont job (batch input)
 .mfm
         Music format (DMP)
 .mft
         Style file (MetaFont source formatter)
 .mg
         Generic module source (Modula-3)
 .mgf
         Font (Micrografx)
 .mgf
         Materials and Geometry Format
 .mgr
         Bitmap graphics (MGR bitmap file)
 .mgx
         Drawing (Designer 4.1)
 .mht
         Message HTML document
 .mhtml
         Message HTML document
 .mi
         Miscellaneous
 .mib
         SNMP MIB file
 .mic
         Data (Microsoft Image Composer)
 .mid
         Music (Musical Instrument Digital Interface)
 .midi
         Music (Musical Instrument Digital Interface)
 .mif
         Data (FrameMaker)
 .miff
         Bitmap graphics (Magick Image File Format)
 .mii
         Datafile (MicroStat-II)
 .mil
         Raster graphics (CALS Group IV Type 2)
 .mime
         Message in MIME format (RFC822)
 .mis
         Mission file (many games)
 .mitsu
         Bitmap graphics (Mitsubishi S340-10 color sublimation printer file)
 .mix
         Object file (Power C)
 .mk
         Makefile
 .mke
         Makefile (MS Windows SDK)
 .mkg
         Makefile
 .mki
         Japanese graphics MAKIchan format (MagView 0.5)
 .mks
         Data (TACT)
 .ml
         ML language source code file
 .ml3
         Project (Milestones 3.x)
 .mlb
         Macro library file (Symphony)
 .mli
         Materials libraries (3D Studio)
 .mlm
         Saved email (Novell GroupWise using WP5.1 format)
 .mm
         Text document (MultiMate Advantage II)
 .mm
         Virtual reality world (Meme)
 .mmf
         Mail message file (MS Mail)
 .mmm
         Multimedia movie format (RIFF RMMP) (MacroMind Director 3.x)
 .mmo
         Memo writer file (RapidFile)
 .mmp
         Output video format from Bravado board
 .mmp
         makmake makefile project (EPOC)
 .mnd
         Menu source (AutoCAD Menu Compiler)
 .mng
         Bitmap graphics (Multiple-image Network Graphics)
 .mng
         Map (DeLorme Map'n'Go)
 .mnt
         Additional (FPT) menu description file (FoxPro)
 .mnu
         Advanced macro (HP NewWave)
 .mnu
         Menu (many)
 .mnx
         Compiled menu (AutoCAD)
 .mnx
         Main (DBF) menu description file (FoxPro)
 .mny
         Account book (MS Money)
 .mo
         Object file (Modula-3)
 .mob
         Device definition (PEN Windows)
 .mod
         Kernel module (Windows 3.x)
 .mod
         Model definitions (EPOC)
 .mod
         Modula-2 language source code file (Clarion Modula-2)
 .mod
         Music (Amiga MODule format) (DMP - FastTracker - MDP - ST)
 .mod
         Spreadsheet (Microsoft Multiplan)
 .moi
         lisez.moi (read.me in French)
 .mol
         MDL Molfile
 .mon
         Monitor description (ReadMail)
 .moo
         MoonRock language source code file (MoonRock)
 .mov
         Movie (AutoCAD AutoFlix)
 .mov
         Timebased multimedia file (Apple QuickTime)
 .moz
         Temporary cache file (Netscape)
 .mp
         Movie (MPEG compressed)
 .mp2
         Sound (MPEG-1 Layer II Audio Stream)
 .mp3
         Sound (MPEG-1 Layer III Audio Stream)
 .mpa
         Sound (MPEG-1 audio stream)
 .mpc
         Calender file (MS Project)
 .mpd
         Monadic predicates (ABC programming language)
 .mpe
         Movie (Moving Pictures Expert Group format)
 .mpeg
         Movie (Moving Pictures Expert Group format)
 .mpg
         Movie (Moving Pictures Expert Group format)
 .mpm
         Mathplan macro (WordPerfect Library)
 .mpnt
         Bitmap graphics (Apple Macintosh MacPaint file)
 .mpp
         Project file (MS Project)
 .mpr
         Generated executable menu file (FoxPro)
 .mpt
         Bitmap graphics (Multipage TIFF)
 .mpv
         View file (MS Project)
 .mpx
         Compiled executable menu file (FoxPro)
 .mrb
         Multiple Resolution Bitmap graphics (MS C/C++)
 .mrc
         Bibliographic data (Machine-Readable Cataloging records)
 .mrk
         CSI markup file (CAD format)
 .mrk
         Windows User Benchmark (Windows 95)
 .mrs
         Macro Resource file (WordPerfect for Win)
 .ms
         Formatted manual page with ms macros
 .ms
         Intermediate assembly file (Modula-3)
 .ms
         Microsoft antivirus report (MSAV)
 .ms
         Worksheet (Maple)
 .msc
         Microsoft C makefile
 .msdl
         Manchester Scene Description Language
 .msg
         Digitized voice file (ZVoice)
 .msg
         Message(s)
 .msn
         Microsoft Network document
 .msp
         Bitmap graphics (Microsoft Paint format)
 .mss
         Manuscript text file (Perfect Writer - Scribble - MINCE - Jove)
 .mst
         Document (MS Test)
 .mst
         Minispecification file (Prosa)
 .mst
         Setup script (MS Windows SDK)
 .msw
         Text document (MS Word)
 .msx
         Compressed CP/M file archive (MSX)
 .mth
         Math file (Derive)
 .mtl
         Wavefront
 .mtm
         Music (MultiTracker Module)
 .mtv
         Bitmap graphics (24bit) (MTV RayTracer)
 .mtw
         Data file (Minitab)
 .mu
         Menu (Quattro Pro)
 .mus
         Sound file (MusicTime - Doom)
 .mvb
         Data (Microsoft Multimedia Viewer)
 .mvf
         Stop frame file (AutoCAD AutoFlix)
 .mvi
         Movie command file (AutoCAD AutoFlix)
 .mvp
         Project (MediaView)
 .mvw
         Log file (Saber LAN)
 .mw
         Text document (MacWrite II)
 .mwf
         Animation (ProMotion)
 .mwii
         Text document (MacWrite II)
 .mwp
         SmartMaster (Lotus Word Pro)
 .mx
         Common matrix routines (Matlab)
 .mx
         Linker information (Modula-3)
 .mx3
         Dynamically linked subroutines (80386/486 MS-Windows) (Matlab)
 .mxl
         Support file (PackRat 5.0)
 .mxt
         Data (MS C)
 .myp
         Presentation (MM Make Your Point)


n

 .nam
        Name Space Modules (Novell NetWare)
 .nap
        Vector graphics (Naplps format) (VideoShow - EnerGraphics)
 .naplps
        Vector graphics (North American Presentation Layer Protocol Syntax)
 .nb
        Text document (Nota Bene)
 .nc
        Graphics (Unidata netCDF)
 .nc
        Instructions for NC (Numerical Control) machine (CAMS)
 .nc
        Preprosessed GOC source code file (non-error-checking version) (GEOS)
 .ncb
        Class browsing information (MS Developer Studio)
 .ncc
        CNC (Computer Numeric Control) control file (CamView 3D)
 .ncd
        Internal tree data (Norton ChangeDirectory)
 .ncm
        Configuration message (Nokia Communicator)
 .ncs
        Netscape Conference Call file (Netscape)
 .ncsa
        Bitmap graphics (Hierarchical Data File) (NCSA)
 .ndb
        Network database (Intellicom - Compex)
 .ndl
        Data (Lotus Notes)
 .ndl
        Inmos hardware network description file 
 .ndl
        Nodelist file
 .ndx
        Index file (dBASE II - III - IV - dBFast)
 .neo
        Bitmap graphics (Atari NeoChrome image file)
 .net
        Network configuration/info file
 .netcdf
        Scientific data Network Common Data Format
 .new
        New info
 .news
        Bitmap graphics (NeWS image file)
 .nff
        Haines Neutral File Format
 .nff
        Neutral File Format (WorldToolKit)
 .nfo
        Filioview database
 .nfo
        Help format (Netware Folio)
 .nfo
        Info file
 .ng
        Online documentation database (Norton Guide)
 .ngo
        NG linker object file (NGML)
 .ngs
        NG compiler source file (NGC)
 .nif
        Binary hardware network initialisation file 
 .nif
        Bitmap graphics (Navy Interchange File Format)
 .niff
        Bitmap graphics (Navy Interchange File Format)
 .nitf
        National Imagery Transmission Format
 .nl
        Norton Desktop Icon Library
 .nlm
        Netware loadable module (Novell Netware)
 .nlx
        Form (FormWorx 3.0)
 .not
        Notation or note
 .note
        Help document (WordPerfect for Mac)
 .now
        Usually README file
 .np
        Project schedule (Nokia Planner) (Visual Planner 3.x)
 .npi
        Source for DGEN.EXE interpreter (dBASE Application Generator)
 .nrf
        Bitmap graphics (Neutral Raster File)
 .ns2
        Data (Lotus Notes)
 .ns3
        Data (Lotus Notes)
 .nsf
        Data (Lotus Notes)
 .nsg
        Data (Lotus Notes)
 .nsh
        Data (Lotus Notes)
 .nss
        Norton screensaver module (NC - NDW Screen Saver)
 .nst
        Music module (NoiseTracker)
 .nsx
        Compound index file (SuccessWare SIX 3.00)
 .nt
        Startup files (Windows NT)
 .ntf
        Data (Lotus Notes)
 .ntr
        Executable ascii text file (strip header and rename) (NetRun)
 .nts
        Executable ascii text file (strip header and rename) (NetSend)
 .nts
        Tutorial (Norton)
 .ntx
        Database index (Clipper 5)
 .nuf
        Message for new users on their 1st call (Procomm Plus)
 .nws
        Info text file (latest news) (ascii)
 .nxt
        Sound (NeXT format)


o

 .o
      Object file (Unix - Atari - GCC)
 .o$$
      Outfile (Sprint)
 .oaz
      Fax (NetFax Manager)
 .ob
      Object cut/paste file (IBM LinkWay)
 .obd
      Binder (MS Binder)
 .obj
      Compiled machine language code (Intel Relocatable Object Module)
 .obj
      Object (Wavefront)
 .obr
      Object browser data file (Borland C++)
 .obs
      Script (ObjectScript)
 .obt
      Template (MS Binder)
 .obv
      Visual interface (ObjectScript)
 .obz
      Wizard (MS Binder)
 .ocf
      Object Craft File (Object Craft)
 .ocr
      Incoming fax transcribed to text (FAXGrapper)
 .oct
      Musical file (Octalizer)
 .ocx
      OLE custom control (Object Linking and Embedding)
 .oda
      ODA document
 .oda
      Raster graphics (CALS Group IV Type 2)
 .odif
      Open Document Interchange Format
 .odl
      Object Definition Language file (MS Developer Studio)
 .ofd
      Form definition (ObjectView)
 .off
      Vector graphics (Object File Format)
 .ofm
      PostScript font description file
 .ofn
      Document (MS Office)
 .oft
      Item template (MS Outlook)
 .ohs
      Outbound History (Bink/+)
 .oid
      Object interaction diagram (Prosa/OM)
 .okt
      Music format (8 channels) (Oktalyzer)
 .olb
      OLE object library
 .olb
      Object library (VAX)
 .old
      Backup file
 .ole
      OLE object
 .oli
      Text file (Olivetti)
 .olk
      Address book (MS Outlook)
 .omd
      Class model (Prosa/OM)
 .omf
      OMF Interchange file
 .oom
      Swap file (Shroom)
 .opa
      Object file (Psion OPL)
 .opl
      OPL language source code file (Psion)
 .opn
      Active options (Exact)
 .opo
      Object file (Psion OPL)
 .opt
      Optimize support file (QEMM)
 .opt
      Options
 .opw
      Organization chart (Org Plus for Windows)
 .opx
      Chart (MS Organization)
 .opx
      Inactive options (Exact)
 .or8
      Oracle 8 database model report (Rational Rose Oracle8)
 .ora
      Parameter file (Oracle)
 .org
      Calendar file (Lotus Organizer)
 .org
      Origin plot (Microcal Origin)
 .oss
      Search result (MS Office)
 .otl
      Outline font description (Z-Soft Type Foundry)
 .otl
      Ventura Publisher's Type Foundry Outline Editor format
 .otx
      Text file (Olivetti Olitext Plus)
 .out
      Output
 .ov1
      Overlay file (part of program to be loaded when needed)
 .ov2
      Overlay file (part of program to be loaded when needed)
 .ovd
      Datafile (ObjectVision)
 .ovl
      Overlay file (part of program to be loaded when needed)
 .ovr
      Overlay file (part of program to be loaded when needed)


p

 .p
       Database source code (Progress)
 .p
       Graphics (Applause picture file)
 .p
       Pascal language source code file
 .p
       Rea-C-Time application parameter file (ReaGeniX code generator)
 .p10
       Tektronix Plot 10 drawing
 .p16
       Music (16 channels) (ProTracker Studio 16)
 .p22
       Patch file (Patch22)
 .p65
       Document (PageMaker 6.5)
 .pa1
       Worktable (PageAhead)
 .pab
       Personal address book
 .pac
       Bitmap graphics (Atari STAD Image)
 .pac
       Package or song (SBStudio II)
 .pad
       Keypad definition (Telemate)
 .paint
       Bitmap graphics B&W (Apple Macintosh MacPaint file)
 .pak
       Compressed file archive (PAK)
 .pal
       Color palette
 .pan
       Printer-specific file (copy to coreldrw.ink) (CorelDraw)
 .par
       Parameter file (Fractint)
 .par
       Parts application (Digitalk PARTS)
 .par
       Permanent output file (Windows 3.x)
 .pas
       Pascal language source code file (Pascal - Delphi)
 .pat
       Bitmap graphics (1bit) (Patent data) (US Patent and Trademark Office)
 .pat
       Hatch patterns (AutoCAD - Photostyler)
 .pat
       Polygon Attribute Table (link geographic locations to databases)
 .pat
       Sound patch (Gravis Ultrasound)
 .pat
       Vector fill files (CorelDraw)
 .pb
       Fax (FAXability Plus)
 .pb
       Phonebook (WinFax Pro)
 .pb
       Proboard configuration files (Proboard)
 .pb
       Setup file (PixBase)
 .pb1
       Document (First Publisher for Windows)
 .pba
       Powerbasic BASIC language source code file (Genus)
 .pbd
       Phone book (FaxNOW! - Faxit)
 .pbi
       Powerbasic include file (Genus)
 .pbi
       Profiler Binary Input (MS Source Profiler)
 .pbk
       Phonebook
 .pbl
       Powerbasic library (Genus)
 .pbm
       Bitmap graphics (Poskanzer's Portable Bit Map format)
 .pbm
       Planar bitmap graphics (XLib)
 .pbo
       Profiler Binary Output (MS Source Profiler)
 .pbt
       Profiler Binary Table (MS Source Profiler)
 .pc
       Text file containing IBM PC specific info
 .pc1
       Bitmap graphics (Atari Degas Image)
 .pc2
       Bitmap graphics (Atari Degas Image)
 .pc3
       Bitmap graphics (Atari Degas Image)
 .pc3
       Custom palette (Harvard Graphics 3.0)
 .pc8
       Ascii text IBM8 character set (NewWave Write)
 .pcb
       P-CAD database (P-CAD)
 .pcc
       Cutout picture vector graphics (ZSoft PC Paintbrush)
 .pcd
       Bitmap graphics (multi-resolution) (Kodak Photo-CD)
 .pcf
       Profiler Command File (MS Source Profiler)
 .pch
       Patch file
 .pch
       Precompiled header (MS C/C++)
 .pcj
       Multimedia authoring tool graphics (IBM's Linkaway-Live)
 .pck
       Pickfile (Turbo Pascal)
 .pcl
       HP-PCL graphics data (HP Printer Control Language)
 .pcp
       Bitmap graphics (PCP file)
 .pcs
       Animated PICTs (Macintosh)
 .pcs
       Picture package (MS PowerPoint - MS ClipArt Gallery)
 .pct
       Bitmap graphics (Macintosh b&w PICT1 - color PICT2)
 .pcw
       Text document (PC Write)
 .pcx
       Bitmap graphics (ZSoft PC Paintbrush format)
 .pda
       Bitmap graphics
 .pdb
       Data (TACT - Packrat 5.0)
 .pdf
       Database Interchange Format (PCAD)
 .pdf
       Graphics file (ED-SCAN 24bit format)
 .pdf
       Package definition file (download info) (Microsoft SMS)
 .pdf
       Portable Document Format (Adobe Acrobat)
 .pdf
       Print device information (Netware)
 .pdg
       Data (Print Shop Deluxe)
 .pdl
       Project Description Language file (Borland C++ 4.5)
 .pds
       Pldasm language source code file (hardware assembly)
 .pds
       Space mission data (Planetary Data System Format) (NASA)
 .pdv
       Printer driver (Paintbrush)
 .pdw
       Document (Professional Draw)
 .pdx
       Printer description (PageMaker)
 .peb
       Program Editor bottom overflow file (WordPerfect Library)
 .ped
       Program Editor delete save (WordPerfect Library)
 .pem
       Program Editor macro (WordPerfect Library)
 .peq
       Program Editor print queue file (WordPerfect Library)
 .per
       Program Editor resident area (WordPerfect Library) (vakioalue)
 .pes
       Program Editor work space file (WordPerfect Library)
 .pet
       Program Editor top overflow file (WordPerfect Library)
 .pex
       Proboard EXecutable program file (Proboard)
 .pfa
       Type 3 font file (unhinted PostScript font)
 .pfb
       Type 1 PostScript font (Adobe Type Manager)
 .pfc
       PF Component
 .pfc
       Text file (First Choice)
 .pfk
       Programmable function keys (XTreePro)
 .pfl
       Portfolio (Lotus Freelance)
 .pfm
       Printer Font Metrics (Windows Type 1 font metric file)
 .pfs
       Database (PFS:FILE) - text file (PFS:Write)
 .pft
       Printer font (ChiWriter)
 .pg
       Page cut/paste file (IBM LinkWay)
 .pgi
       Printer Graphics File device driver (PGRAPH library)
 .pgl
       Vector graphics (HP Plotter)
 .pgm
       Bitmap graphics (PBM graymap)
 .pgm
       Program (Signature)
 .pgp
       Encrypted file (Pretty Good Privacy)
 .pgs
       Manual page (man4dos)
 .ph
       Optimized .goh include file (Geoworks)
 .ph
       Perl header file
 .ph
       Phrase-table (MS C/C++)
 .phd
       PolyHedra Database
 .phm
       Phone book (DN - Lync)
 .phn
       Phone list (UltraFax - QmodemPro)
 .pho
       Phone database (Metz Phone for Windows)
 .phr
       Phrases (LocoScript)
 .pi1
       Bitmap graphics (Atari Degas Image)
 .pi2
       Bitmap graphics (Atari Degas Image)
 .pi3
       Bitmap graphics (Atari Degas Image)
 .pic
       Bitmap graphics (Macintosh) (b&w PICT1 - color PICT2)
 .pic
       Bitmap graphics (PIXAR picture file)
 .pic
       Bitmap graphics (Pictor page format) (many)
 .picio
       Bitmap graphics (PIXAR picture file)
 .pics
       Animated PICT files (Macintosh)
 .pict
       Bitmap graphics (Apple Macintosh PICT file) (b&w PICT1 - color PICT2)
 .pict2
       Bitmap graphics (Apple Macintosh PICT file)
 .pid
       Process ID file (Unix)
 .pif
       Graphics metafile (OS/2)
 .pif
       Program Information File (Windows 3.x)
 .pif
       Vector graphics GDF format (IBM mainframe computers)
 .pim
       Pascal text mode image file (Ultimate Draw)
 .pin
       Game data (Epic Pinball)
 .pit
       Compressed Macintosh file archive (PackIt)
 .pix
       Bitmap graphics (24bit RGB RLE) (Alias image file)
 .pix
       Bitmap graphics (Inset Systems format)
 .pixar
       Bitmap graphics (PIXAR picture file)
 .pj
       Bitmap graphics (HP PaintJet PCL graphics file)
 .pj
       Project (CA-SuperProject)
 .pjt
       Additional (FPT) project description file (FoxPro)
 .pjt
       Project (Visual C++)
 .pjx
       Main (DBF) project description file (FoxPro)
 .pjxl
       Bitmap graphics (HP PaintJet XL PCL graphics file)
 .pk
       Packed bitmap font file (TeX DVI drivers)
 .pka
       Compressed file archive (PKArc)
 .pkg
       Installer script (Next)
 .pkg
       Package (AppleLink - MS Developer Studio)
 .pkg
       database (P-CAD)
 .pkr
       Public Keyring (PGP)
 .pkt
       Fidonet message packet
 .pkt
       Readable contents of .pk (TeX font)
 .pl
       Palette (Harvard Graphics)
 .pl
       Perl script language source code file
 .pl
       Prolog language source code file
 .pl
       Property List font metric file (TeX)
 .pl1
       Room plan (3D Home Architect)
 .pl3
       Chart palette (Harvard Graphics 3.0)
 .plb
       Library (FoxPro - P-CAD)
 .plc
       Add-in file (functions - macros - applications) (Lotus 1-2-3)
 .plc
       Database (P-CAD)
 .plg
       Build log (MS Developer Studio)
 .pll
       Prelinked library (CA Clipper)
 .pln
       Spreadsheet (WordPerfect for Win)
 .plot
       Vector graphics (Unix Plot(5) format)
 .plt
       Palette
 .plt
       Paper format (Page Magic 2.0)
 .plt
       Pre-linked transfer file (Clipper 5)
 .plt
       Software platform file (Geoworks Glue, EPOC)
 .plt
       Table for .pll (CA Clipper)
 .plt
       Vector graphics (HPGL plotter) (AutoCAD Plot)
 .ply
       Data (PopMail)
 .ply
       Presentation screen (Harvard Spotlight)
 .ply
       ZipPack
 .pm
       Bitmap graphics (8bit text) (X Window PixelMap)
 .pm
       Bitmap graphics (Presentation Manager)
 .pm
       Perl
 .pm3
       Document (PageMaker 3)
 .pm4
       Document (PageMaker 4)
 .pm5
       Document (PageMaker 5)
 .pm6
       Document (PageMaker 6)
 .pma
       Data (Performance Monitor)
 .pmc
       Data (Performance Monitor)
 .pmc
       Graphics (A4TECH Scanner)
 .pmi
       Program manager information (OS/2)
 .pml
       Data (Performance Monitor)
 .pmm
       Program file (Amaris BTX/2)
 .pmr
       Data (Performance Monitor)
 .pmw
       Data (Performance Monitor)
 .pn3
       Printer device driver (Harvard Graphics 3.0)
 .pnf
       Bitmap graphics (Portable Network graphics Frame) (standalone stream)
 .pnf
       Precompiled setup information (Windows)
 .png
       Bitmap graphics (Portable Network Graphics)
 .pnm
       Bitmap graphics (PBM Portable aNyMap)
 .pnt
       Bitmap graphics (Apple MacPaint format)
 .pnt
       Pointlist segment (FTN software)
 .pnt
       Qwk reader pointer file (MarkMail 2.x)
 .pnt
       Vector point data (ARC format)
 .pntg
       Bitmap graphics B&W (Apple Macintosh MacPaint file)
 .poh
       Optimized .goh include file (Geoworks)
 .pol
       Polygon Models Format (InnovMetric Software)
 .poo
       String pool (INITeX)
 .pop
       Messages index (PopMail)
 .pop
       Pop-up menu object (dBASE Application Generator)
 .pot
       Continuous potential image (Fractint)
 .pot
       Template (MS PowerPoint)
 .pov
       Raytraced graphics image (Persistance Of Vision)
 .pow
       Instrument or song file (PowerChords)
 .pp
       Compressed Amiga file archive (PowerPacker)
 .pp4
       Bitmap graphics (Picture Publisher 4)
 .ppa
       Add-in (MS PowerPoint)
 .ppb
       Button bar for Print Preview (WordPerfect for Win)
 .ppd
       PostScript printer description file (PageMaker)
 .ppk
       Archive (using for many distributives) (PPK)
 .ppl
       Polaroidpaletteplus ColorKey device driver (Harvard Graphics 3.0)
 .ppm
       Bitmap graphics (PBM Portable Pixel Map)
 .ppo
       Preprocessor output (CA Clipper 5.x)
 .ppp
       Publication (PagePlus)
 .pps
       Slide show (MS PowerPoint)
 .pps
       Storyboard (Personal Producer)
 .ppt
       Presentation (MS PowerPoint)
 .pr
       Bitmap graphics (Sun raster file)
 .pr1
       Data file (Packrat 4.0)
 .pr2
       Data file (Packrat 4.x)
 .pr2
       Presentation (Aldus Persuasion 2.x)
 .pr2
       Printer driver (dBASE IV)
 .pr3
       Postscript printer driver (dBASE IV)
 .pr3
       Presentation (Aldus Persuasion 3.x)
 .prc
       Processes (Rational Rose)
 .prd
       Printer driver (many)
 .pre
       Bitmap graphics (CMYK image) (Stork format)
 .pre
       Presentation (Lotus Freelance)
 .pre
       Settings (Programmer's WorkBench - MS C/C++)
 .prf
       Bitmap graphics (Pixel Run Format) (Improces - Fastgraph)
 .prf
       Data file (CheckIt Pro 1.0)
 .prf
       Printer driver (dBASE IV)
 .prf
       Profiler output
 .prg
       Program (Atari)
 .prg
       Program source (dBASE IV - FoxPro - CA Clipper - dBFast)
 .pri
       Printer definitions (LocoScript)
 .prj
       Project
 .prm
       Parameters
 .prn
       Printer driver (Signature)
 .prn
       Text file (Lotus 1-2-3 - Symphony)
 .prn
       Usually printer output file
 .pro
       Graphics profile file (DOS)
 .pro
       Profile (configuration data)
 .pro
       Prolog language source code file
 .proj
       Project File (Interface Builder) (NeXT)
 .prp
       Model properties (Rational Rose)
 .prr
       The Perfect Resume data file (Perfect Resume)
 .prs
       Presentation (Harvard Graphics Win)
 .prs
       Printer Resource eg. fonts (WordPerfect for Win)
 .prs
       Procedure (dBASE IV)
 .prt
       Component (P-CAD)
 .prt
       PTC Pro/ENGINEER part
 .prt
       Printer driver (Dr.Halo)
 .prvkr
       Private keyring (PGP)
 .prx
       Compiled program (FoxPro)
 .ps
       Adobe Postscript document (text/graphics)
 .ps2
       Adobe Level II Postscript document (text/graphics)
 .psa
       Archive (Pretty Simple Archive) (GNU PSA.OUT)
 .psd
       Bitmap graphics (Adobe Photoshop format)
 .psd
       Definition file (Periscope Debugger)
 .pse
       Bitmap graphics (IBM printer Page SEgment)
 .pseg
       Bitmap graphics (IBM printer Page SEgment)
 .psf
       Outline PostScript printer font (ChiWriter)
 .psid
       Postscript image data (text/graphics) (ascii file)
 .psm
       Music format (Protracker Studio Module) (Protracker - MASI)
 .psm
       Symbol table of IDE (Turbo Pascal)
 .psn
       Presentation file (Sound Script)
 .psp
       Procedure (Prodea Synergy)
 .pst
       Paste buffer (Lahey Fortran)
 .pst
       Personal Folder File (Microsoft Outlook)
 .pst
       Postbox file (BMail)
 .pt
       Game crack (Player Tools)
 .pt
       Kodak Precition Color Management System
 .pt
       Sound (Pitch Track)
 .pt3
       Device driver (Harvard Graphics 3.0)
 .pt3
       Template (PageMaker 3)
 .pt4
       Template (PageMaker 4)
 .pt5
       Template (PageMaker 5)
 .ptb
       Script (PubTech BatchWorks)
 .ptl
       Petal (Rational Rose 98)
 .ptm
       Macro (PubTech BatchWorks)
 .ptm
       Music format
 .ptm
       Template (Page Magic 2.0)
 .ptr
       Cursor image file (OS/2 PTR file)
 .ptr
       Qwk reader pointer file (QMail)
 .ptu
       Performer Terrain Utilities
 .ptx
       Bitmap graphics (Printronix graphics file)
 .pty
       Properties (Rational Rose 98)
 .pub
       Page template (MS Publisher)
 .pub
       Public keyring (Pretty Good Privacy)
 .pub
       Publication (PageMaker - Ventura Publisher - 1st Publisher)
 .pubkr
       Public key ring (PGP)
 .put
       Compressed file archive (PUT)
 .put
       Graphics (WScan)
 .puz
       Puzzle file (BrainsBreaker Puzzle)
 .puzz
       Bitmap graphics (8bit) (X11 Puzzle)
 .puzzle
       Bitmap graphics (8bit) (X11 Puzzle)
 .pv
       Analysis data (Phase Vocorder)
 .pvd
       Script (Instalit)
 .pvl
       Library (Instalit)
 .pvt
       Local Fidonet pointlist (FTN software)
 .pvu
       Paleoenvironmental data (PaleoVu)
 .pw
       Text document (Professional Write)
 .pwd
       Text document (Microsoft Pocket Word)
 .pwl
       Password List
 .pwp
       Text document (Professional WritePlus)
 .pwz
       Wizard (MS PowerPoint)
 .px
       Primary database index (Paradox)
 .pxl
       Pixel data (TeX driver)
 .pxl
       Script (PiXCLscript)
 .pxl
       Spreadsheet (Microsoft Pocket Excel)
 .pxp
       Process file (3D Studio)
 .pxr
       Bitmap graphics (Pixar image) (Photoshop)
 .py
       Python script file
 .pyc
       Compiled Python script file
 .pzd
       Default settings (Pizazz Plus)
 .pzi
       Graphics (Pizazz Plus)
 .pzl
       Bitmap graphics (8bit) (Unix Puzzle)
 .pzo
       Overlay (Pizazz Plus)
 .pzp
       Palette (Pizazz Plus)
 .pzs
       Settings (Pizazz Plus)
 .pzt
       Transfer file (Pizazz Plus)
 .pzx
       Swap file (Pizazz Plus)


q

 .q
      Win95 fax queue
 .q0
      Bitmap graphics (24bit) (Japanese Q0 image format)
 .qad
      Document (PF QuickArt)
 .qag
      Quick Access Group (Norton Desktop)
 .qap
      Application (Omnis Quartz)
 .qbe
      Saved query (Query By Example) (dBASE IV - Quattro Pro)
 .qbo
      Compiled query (dBASE IV)
 .qbw
      Spreadsheet (QuickBooks for Windows)
 .qcp
      Digitally encoded voice (Qualcomm QCELP recoder and player)
 .qd0
      Data file - segment 10 (Omnis Quartz)
 .qd1
      Data file - segment 1 (Omnis Quartz)
 .qd2
      Data file - segment 2 (Omnis Quartz)
 .qd3
      Data file - segment 3 (Omnis Quartz)
 .qd3
      QuickDraw 3D Metafile (QuickDraw)
 .qd3d
      QuickDraw 3D Metafile (QuickDraw)
 .qd4
      Data file - segment 4 (Omnis Quartz)
 .qd5
      Data file - segment 5 (Omnis Quartz)
 .qd6
      Data file - segment 6 (Omnis Quartz)
 .qd7
      Data file - segment 7 (Omnis Quartz)
 .qd8
      Data file - segment 8 (Omnis Quartz)
 .qd9
      Data file - segment 9 (Omnis Quartz)
 .qdk
      Backup of startup files created by Optimize (QEMM)
 .qdv
      Bitmap graphics (8bit) (Random Dot QDV file)
 .qef
      Query file (Q+E for MS Excel)
 .qfc
      Compressed file archive
 .qfx
      Fax (QuickLink)
 .qic
      Backup set (MS Backup)
 .qlb
      Quick library (BASIC PDS - MS C/C++)
 .qlc
      ATM Type 1 fonts script (Adobe Type Manager)
 .qlp
      Printer driver (QuickLink)
 .qm4
      Options or services file (QMail 4.x Mail Door)
 .qpr
      Generated query program (FoxPro)
 .qpr
      Print queue device driver (OS/2)
 .qpx
      Compiled executable QBE query file (FoxPro)
 .qrs
      Equation Editor support file (WordPerfect for Win)
 .qrt
      Bitmap graphics (24bit) (QRT Raytracer)
 .qry
      Query (dBASE IV)
 .qsn
      QuickScan data (TapCIS)
 .qt
      QuickTime movie (animation)
 .qtc
      QuickTime Conferencing
 .qtk
      Bitmap graphics (QuickTake digital camera)
 .qtv
      Movie (QuickTime Virtual Reality)
 .qtvr
      Movie (QuickTime Virtual Reality)
 .que
      Queue object (Scheduler)
 .qwk
      Qwk reader message file
 .qxd
      Document (QuarkXPress)
 .qxl
      Element library (QuarkXPress)
 .qxt
      Template (QuarkXPress)


r

 .r
      Ratfor file (FORTRAN preprosessor)
 .r2d
      Data file (Reflex 2)
 .r8
      Raw graphics (one byte per pixel) plane one (PicLab)
 .r8
      Red channel image data (24bit 3D animation) (Cubicomp PictureMaker)
 .r8p
      Pcl 4 bitmap font file (Intellifont)
 .ra
      Audio file (RealAudio)
 .ra
      Data file (Remote Access)
 .rad
      2-op FM music (Reality AdLib Tracker)
 .rad
      Radience
 .ram
      RealAudio Metafile (RealAudio)
 .rar
      Compressed file archive (RAR)
 .ras
      Bitmap graphics (Sun raster image)
 .rast
      Bitmap graphics (Sun raster image)
 .rat
      Datafile (RATS)
 .raw
      Bitmap graphics (Raw 24-bit RGB)
 .raw
      Sound (Raw sound data) (PCM)
 .ray
      Rayshade
 .rbf
      Datafile (Rbase)
 .rc
      Configuration record (Emacs)
 .rc
      Resource script (MS C/C++ - Borland C++ - Resource WorkShop)
 .rc2
      Not editable resources (MS Developer Studio)
 .rcg
      Netscape newsgroup file (netsc.rcg)
 .rct
      Resource template (MS Developer Studio)
 .rd3
      Graphics (Ray Dream Designer 3)
 .rdef
      UI resource file (old) (Geoworks)
 .rdf
      Compiled UIC source code (Geoworks UI Compiler)
 .rdi
      Device-independent bitmap file (RIFF RDIB format)
 .rdx
      Datafile (Reflex)
 .rec
      Archivation protocol (ARCSERVE)
 .rec
      Datafile (EpiInfo)
 .rec
      Macro (Windows Recorder)
 .rec
      Record (Sprint)
 .red
      Path info (Clarion Modula-2)
 .ref
      Cross-reference
 .reg
      Registration information or key
 .rem
      Remarks
 .rep
      Reply file (Qwk reader)
 .rep
      Report file
 .req
      Request
 .res
      Compiled resource (MS C/C++ - Borland C++)
 .res
      Resign conferences file (XBoard)
 .res
      Resource
 .rev
      Revision file (Geoworks)
 .rex
      Executable file (old format) (PharLab)
 .rex
      Report definition (Oracle)
 .rex
      Rexx language source code file (Rexx)
 .rez
      Resource file
 .rf
      Bitmap graphics (Raster file)
 .rfm
      Rich music format
 .rft
      DCA/RFT Revisable Format Text file (IBM DisplayWrite 4.0-5.1)
 .rg
      Bitmap graphics (1bit B&W 4bit CMYK) (Raster Graphics format)
 .rgb
      Bitmap graphics (Raw 24bit Red-Green-Blue) (many)
 .rgx
      Symbol tables etc. info (ReaGeniX code generator)
 .rh
      Resource header (Borland C++, Visual C++)
 .ri
      Data (Lotus 1-2-3)
 .rib
      Graphics (Renderman Interface Bytestream) (3D Reality)
 .ric
      Fax (Ricoh)
 .rif
      Bitmap graphics (Resource Interchange File Format)
 .riff
      Bitmap graphics (Resource Interchange File Format)
 .rip
      Graphics (Remote Access)
 .rip
      Program crash report (Quincy)
 .rip
      Telegrafx Remote Imaging Protocol (Maximus 3.0)
 .rix
      Bitmap graphics (RIX Softworks Paint Tool ColoRIX file)
 .rkv
      Compressed file archive (RKIVE)
 .rl4
      Bitmap graphics
 .rl8
      Bitmap graphics
 .rla
      Bitmap graphics (Wavefront raster image file)
 .rlb
      Bitmap graphics (Wavefront raster image file)
 .rlb
      Data (Harvard Graphics Win)
 .rlc
      Bitmap graphics (Run Length RLC file)
 .rld
      Temporary file (Norton Commander 5.0)
 .rle
      Bitmap graphics (Utah Run-Length Encoded image file)
 .rlz
      Realizer source code file (CA-Realizer)
 .rm
      Audio file (RealAudio)
 .rmf
      Rich Music Format (Beatnik)
 .rmi
      Midi music (RIFF RMID format)
 .rmk
      Makefile (CA Clipper RMake)
 .rmp
      Audio file (RealAudio)
 .rn
      Xpl program (Nota Bene)
 .rnd
      Rendering Slide (AutoCAD AutoShade)
 .rng
      Ringing tone (Nokia Communicator)
 .rnk
      Diap-up shortcut
 .rno
      Runoff file (VAX)
 .roff
      Unformatted manual page (Roff/nroff/troff/groff)
 .rol
      Roland music file (Adlib)
 .rom
      Read Only Memory image (emulators - AONs)
 .rot
      3D image (Rotater)
 .rov
      Game data (Rescure Rover)
 .rpb
      Data report file (CP Backup)
 .rpd
      Database (RapidFile)
 .rpf
      Pattern (AutoCAD)
 .rpl
      Document (Replica)
 .rpl
      Reply message
 .rpl
      Text document (Replica)
 .rpm
      Plugin (RealAudio)
 .rpt
      Report
 .rs
      Data file (Amiga Resource - Reassembler)
 .rs_
      Resource fork of a Macintosh file (Mac-ette)
 .rsc
      Compiled resource(s)
 .rsg
      Compiled resource header (EPOC)
 .rsl
      Resource Library (PC Tools Win)
 .rsp
      Response file
 .rsrc
      Resource
 .rss
      Resource source file (EPOC)
 .rt
      Rich text
 .rtf
      Text document (Rich Text Format) (many)
 .rtfd
      RTF-Packet (NeXT)
 .rtl
      Bitmap graphics (HP Raster Transfer Language) (HP colour printers)
 .rtl
      Run-Time library (Norton Utilities)
 .rtl
      Text file
 .rtp
      Software update file (.RTPatch)
 .rts
      Runtime library (CA-Realizer)
 .rtx
      Text document (MIME Richtext format)
 .rul
      Rules (Echo-conference)
 .run
      Batch file (PC Tools)
 .rus
      Russian text
 .rvw
      Review
 .rws
      Resource Workshop Symbol file (Borland C++)
 .rwx
      MEME Shape File
 .rwx
      Script (Criterion RenderWare)
 .rxd
      Datafile (Reflex 1)


s

 .s
        Assembly language source code file.s (Unix)
 .s
        Foreign assembly source file (Modula-3)
 .s
        Macro source file (MultiEdit)
 .s
        Scheme language source code file
 .s$$
        Temporary sort file (Sprint)
 .s1k
        S1000 Simnet Format
 .s3i
        Sample file (Digiplayer - ST3)
 .s3m
        Music (16 channels) (Scream Tracker III)
 .saf
        Spatial Archive Interchange Format
 .saif
        Spatial Archive Interchange Format
 .sal
        Datafile (SORITEC)
 .sam
        Text file (Samna - Lotus Ami/Ami Pro)
 .sar
        Compressed file archive (SAR)
 .sas
        SAS source code file (VMS)
 .sav
        Saved backup or configuration data
 .sav
        Saved game situation (eg. NetHack)
 .sb
        Audio file (signed byte)
 .sbd
        Data file (Storyboard Editor)
 .sbi
        Sound Blaster Instrument (Creative Labs)
 .sbk
        Emu SoundFont Bank (AWE32 Bank) (Convert (c) Villena)
 .sbk
        Toolbook (Asymetrix ToolBook)
 .sbl
        library (Stonu Brook Pascal)
 .sbp
        Dml program (Superbase 4)
 .sbr
        Support file (Source Browser)
 .sbt
        Notes related to record (Suberbase 4 Windows)
 .sc
        Display driver (Framework II)
 .sc
        PAL script (Paradox)
 .sc2
        Document (MS Schedule+ 7.x)
 .sc3
        Renamed dBASE III screen mask file (dBASE IV)
 .sc3
        Screen device driver (Harvard Graphics 3.x)
 .sca
        Datafile (SCA)
 .scan
        Bitmap graphics (Thunderscan image file)
 .scc
        Bitmap graphics (MSX picture)
 .scd
        Bitmap graphics (SCODL Scan Conversion Object Description Language)
 .scd
        Contacts (MS Schedule+ 7.x)
 .scf
        Multimedia show (ScoreMaker)
 .scf
        Shell Command File (Windows Explorer)
 .scf
        Spelling checker configuration (Symphony)
 .scg
        Bitmap graphics (ColoRIX)
 .sch
        Project schedule (Schedule Publisher - MS Schedule+ 7.x)
 .sch
        Scheme (P CAD - Orcad)
 .sci
        Bitmap graphics (Scitex Continuous Tone (CT2T) image file)
 .sci
        Fax (SciFax)
 .sci
        System Configuration Information
 .scm
        Movie (Lotus ScreenCam)
 .scm
        Scheme language source code file
 .scn
        SCeNe RTrace
 .scn
        Screen dump or file (Kermit)
 .sco
        Score (best results)
 .scodl
        Bitmap graphics (Agfa slide file)
 .scp
        Bitmap graphics (ColoRIX)
 .scp
        Script (BITCOM)
 .scr
        Bitmap graphics (ColoRIX or Sun rasterfile)
 .scr
        Debug source code file (DOS Debug)
 .scr
        Fax image
 .scr
        Screen (source) file (Forth)
 .scr
        Screen font (LocoScript)
 .scr
        Screen saver (Windows 3.x)
 .scr
        Screen snapshop (Microsoft Screen Capture format)
 .scr
        Script (1st Reader - Kermit - TeleMate - AutoCAD)
 .sct
        Additional (FPT) screen description file (FoxPro)
 .sct
        Bitmap graphics (Scitex CT bitmap)
 .scu
        Bitmap graphics (ColoRIX)
 .scx
        Chart (Stanford Chart)
 .scx
        Graphics bitmap (ColoRIX)
 .scx
        Main (DBF) screen description file (FoxPro)
 .scy
        Security file (ReaGeniX)
 .scz
        Data (Wingz)
 .sd
        Sound (Entropic Sound Data format)
 .sda
        Software Distribution Network file archive description
 .sdf
        Source definition file (Sourcer)
 .sdf
        System Data Format file (fixed lenght ascii text)
 .sdi
        Software Distribution Network Info file
 .sdk
        Roland S-550/S-50/W-30 Disk Image
 .sdl
        Parsys hardware network description file 
 .sdl
        Scene Description Language (Alias Wavefront)
 .sdl
        SmartDraw library
 .sdml
        Spacial Data Modeling Language
 .sdn
        Software Distribution Network compressd file archive (pak251.exe)
 .sdr
        Music (Sounder)
 .sdr
        SmartDraw drawing
 .sds
        MIDI Sample DUMP Standard File
 .sdt
        SmartDraw template
 .sdts
        Spatial Data Transfer Standard
 .sdw
        Vector graphics (Ami Draw)
 .sdx
        Sample DUMP Exchange File
 .sea
        Self-extracting compressed Macintosh file archive (Compact Pro)
 .sec
        Diskreet encrypted file (Diskreet)
 .sec
        Secret key ring file (Pretty Good Privacy)
 .sec
        Secured animation file (Disney Animation Studio)
 .sep
        Printer separator page
 .seq
        Animation file (Atari)
 .seq
        Sequential Instruction File (Bubble Chamber)
 .ses
        Session info (Clarion Modula-2)
 .set
        Configuration (1st Reader)
 .set
        Driver sets created by Install (Symphony)
 .set
        Setup data or info
 .sf
        IRCAM Sound File (CSound package - MixView sound sample editor)
 .sf
        WPS attribute storage (OS/2 WorkPlace Shell)
 .sfb
        HP Soft font
 .sff
        Scene File Format
 .sfi
        Graphics (SIS Framegrabber)
 .sfi
        Printer font (HP LaserJet landscape) (Ventura Publisher)
 .sfl
        PCL 4 bitmap font (landscape) (Intellifont - Ventura Publisher)
 .sfn
        Font (SPX)
 .sfo
        Bitstream font file - fontware format
 .sfp
        Pcl 4 bitmap font (portrait) (Intellifont) (Ventura Publisher)
 .sfs
        Pcl 5 scalable font file (Intellifont)
 .sft
        Screen font (ChiWriter)
 .sfw
        Graphics (Seattle Film Works)
 .sfx
        Self-extracting file archive script (RAR)
 .sg1
        Graphics (Stanford Graphics)
 .sgd
        Help file (Lahey Blackbeard)
 .sgf
        Document with graphics (Starwriter)
 .sgi
        Bitmap graphics (Silicon Graphics Image)
 .sgm
        IETF SGML document (Standard Generalized Markup Language)
 .sgml
        IETF SGML document (Standard Generalized Markup Language)
 .sgp
        Statistics (STATGRAPHICS Plus)
 .sgt
        Save/get keyboard macro (Signature)
 .sgx
        Help file index (Lahey Fortran)
 .sh
        Shell script (unix) (ascii) (SHAR)
 .sh3
        Presentation (Harvard Graphics 3.0)
 .shar
        Shell Archive (Unix) (script)
 .shb
        Background (CorelShow)
 .shb
        Presentation (Corel Show)
 .shb
        Shortcut into a document (Windows 95)
 .shd
        Spool file (Windows95)
 .shg
        Bitmap graphics (Segmented HyperGraph)
 .shk
        Compressed Apple II file archive (ShrinkIt)
 .shm
        Shell macro (WordPerfect Library)
 .shp
        Icon library (Printmaster)
 .shp
        Shape file and source file for text fonts (AutoCAD)
 .shr
        Unix Shell ARchive (ascii) (SHAR)
 .shs
        Shell scrap object (Windows 95)
 .shtml
        HTML with server side includes
 .shw
        Presentation (Harvard Graphics - CorelShow)
 .shx
        Shape entities (AutoCAD)
 .si
        Graphics (SoftImage)
 .sid
        C64 tunes and sound effects file (PlaySID)
 .sif
        Setup Installation File
 .sif
        Vector data (ISIF format)
 .sig
        Current program settings (Signature)
 .sig
        Signature file (ThunderByte AntiVirus - PopMail - PGP)
 .sik
        Backup file (Sicherungskopie) (MS Word)
 .sim
        SIMPLE script source (Telix)
 .sir
        Bitmap graphics (Solitaire file)
 .sis
        Software installation file (Psion)
 .sit
        Compressed Macintosh file archive (UnStuff)
 .six
        Bitmap graphics (DEC LN03+ Sixel file)
 .sixel
        Bitmap graphics (DEC LN03+ Sixel file)
 .skcard
        Datafile (Starfish SideKick)
 .skr
        Private (secret) keyring (PGP)
 .sky
        SYLK Spreadsheet file (Multiplan)
 .sl
        S-Lang language source code file
 .slb
        Slide library (AutoCAD)
 .slb
        Symbols library (P-CAD)
 .slc
        Compiled SALT script (Telix)
 .sld
        Slide (AutoCAD)
 .sli
        Slide (MAGICorp Slide Service)
 .slk
        Data format (Sylk Symbolic Link format)(Excel - MultiPlan)
 .sll
        Sound file
 .slt
        Salt Script Application Language script source (Telix)
 .sm
        Maillist (SoftSpoken Mailer)
 .sm
        Script (ScriptMaker)
 .sm
        Smalltalk language source code file
 .sm
        Text document (Samna Word)
 .smf
        Fax (SMARTFAX)
 .smm
        Macro (Ami Pro)
 .smn
        Font (ParaGraph's WorkScript format)
 .smp
        Sound (SaMPleVision)
 .smt
        Text file (Smart Ware II)
 .sn
        Compressed song file (Sound Club editor)
 .snd
        Sound file (Sun/NeXT/Tandy/Apple Macintosh Sound file formats)
 .sng
        Song (midi sound) (Midisoft Studio - Prism)
 .sno
        Snobol4 language source code file
 .snp
        Book-shelf for .BOO (READIBM)
 .snp
        Output video format from Computer Eyes equipment
 .so
        Shared object (Fortran 90)
 .sol
        MATRA prelude solids
 .sol
        Solution eg. game walkthroughs
 .som
        Network serial numbers (Quattro Pro)
 .som
        Sort information (Paradox)
 .son
        Song (SBStudio II)
 .sou
        Sound data (SBStudio II)
 .sp
        Compressed file archive (Splint)
 .spc
        Bitmap graphics (Atari compressed Spectrum file)
 .spc
        Program (MS Multiplan)
 .spc
        Temporary file (WordPerfect for Win)
 .spc
        Text to speech
 .spd
        Scalable font (Speedo) (Harvard Graphics 3.0)
 .spf
        Slide presentation file (EnerGraphics)
 .spg
        Glossary (Sprint)
 .sph
        Sphere
 .spiff
        Graphics (Still Picture Interchange File Format)
 .spk
        Compressed file archive (Spark) (Acorn)
 .spl
        Compressed file archive (Splint)
 .spl
        Customized printer driver (Sprint)
 .spl
        Personal spell dictionary (Signature)
 .spl
        Sample
 .spl
        Splash (Macromedia)
 .spl
        Spool file (Windows 3.x printing)
 .spm
        Data (WordPerfect)
 .spot
        Bitmap graphics (SPOT satellite image file)
 .spp
        Printer file (Sprint)
 .spr
        Animation (Sizzler)
 .spr
        Document letter (Sprint)
 .spr
        Generated executable screen file (FoxPro)
 .spr
        Spreadsheet (Psion Series 3)
 .spr
        Sprite (graphics image) (many - Story Board)
 .sprite
        Animation (Sizzler)
 .sps
        SPSS language source code file (VAX/VMS)
 .sps
        Screen driver (Sprint)
 .spt
        Data support file (MITAC disk/system management utility pack)
 .spt
        Spitbol language source code file
 .spt
        Split (one part of multi-part file)
 .spt
        Support file (MITAC disk/system management utility pack)
 .spu
        Bitmap graphics (Atari compressed Spectrum file)
 .spw
        Worksheet (SigmaPlot)
 .spx
        Compiled executable screen file (FoxPro)
 .spx
        Screensaver (Screen Peace) (Windows)
 .sqd
        Squish message base (Squish)
 .sqi
        Squish message base index (Squish)
 .sql
        SQL report or query
 .sql
        Squish message base last read pointers (Squish)
 .sqz
        Compressed file archive (Squeeze)
 .sr
        Bitmap graphics (Sun Rasterfile)
 .src
        Source (DataFlex, Multi-Edit)
 .srf
        Bitmap graphics (Sun Raster File)
 .srp
        Script (QuickLink)
 .ss
        Bitmap graphics (Splash)
 .ss
        Screen saver (DN)
 .ssd
        Datafile (SAS/PC)
 .ssh
        Secure Shell document (DataFellows)
 .ssi
        HTML with server side includes
 .ssp
        Datafile (SAS Transport)
 .ssq
        ODBC script
 .sst
        Satellite image data (AVHRR file) (IDIDAS - SSTMAP - IMGMAP)
 .st
        Instrument library (Scream Tracker)
 .st
        Smalltalk language source code file (Little Smalltalk)
 .st
        Stamp (NeoPaint)
 .sta
        Data file (Statistica)
 .sta
        Saved state (Reflection 4.0)
 .sta
        Stack (Spinmaker Plus)
 .stb
        Stub library (Genus GX Kernel)
 .std
        Standard (something..) (LocoScript)
 .std
        State Transition Diagram graphics file (Prosa)
 .step
        ISO-10303 STEP product data
 .stf
        Compressed file archive (ShrinkToFit)
 .stl
        Stereolithography Interface Format
 .stm
        Music (4 channels) (Scream Tracker II)
 .stm
        State Transition Diagram model file (Prosa)
 .sto
        Pascal stub OBJ file (Genus GX Kernel)
 .stp
        ISO-10303 STEP product data
 .str
        Gate3 table structure file
 .str
        Structure list object file (dBASE Application Generator)
 .sts
        Project status info (MS C/C++)
 .sts
        Song format (Scream Tracker)
 .stw
        Data file (SmartTerm for Windows)
 .stx
        Electronic book (SmarText)
 .stx
        Music format
 .stx
        Tax form (CA-Simply Tax)
 .sty
        Style library or sheet (many text and graphics programs)
 .sub
        Component package (Rational Rose)
 .sui
        Suit library (Simple User Interface Toolkit)
 .sum
        Summary
 .sun
        Raster graphics (Sun Rasterfile)
 .suniff
        Bitmap graphics (Sun TAAC Image File Format)
 .sup
        Bitmap graphics (Startup screen)
 .sup
        Supplementary dictionary (WordPerfect for Win)
 .svd
        Document autosave file (MS Word)
 .svf
        Vector graphics (Simple Vector Format) (CAD programs)
 .svg
        Glossary autosave file (MS Word)
 .svq
        Music file
 .svr
        Virtual world (compressed) (WWW)
 .svs
        Style sheet autosave file (MS Word)
 .svx
        Sound (Amiga 8SVX format)
 .sw
        Audio file (signed word)
 .swa
        Music (MPEG-1 Layer III with special header) (Macromedia Shockwave)
 .swf
        Flash (Macromedia)
 .swg
        SWAG Pascal Snippets file (SWAG Reader)
 .swp
        Document backup (Sprint)
 .swp
        Swap file
 .sxp
        Process file (3D Studio)
 .sy1
        Smartpix symbol library (Ami Pro)
 .sy3
        Symbol file (Harvard Graphics 3.x)
 .syd
        Backup (QEMM - Sysedit)
 .syk
        SYLK spreadsheet format (Excel)
 .sylk
        SYLK spreadsheet format (Excel)
 .sym
        Component symbols (P-CAD)
 .sym
        Graphics symbols (Harvard Graphics 2.0 - MS Windows SDK)
 .sym
        Precompiled headers (Borland C++)
 .sym
        Program symbol table (many compilers and linkers)
 .syn
        Bitmap graphics (SDSC Synu image file)
 .syn
        Synonym file (MS Word 5)
 .synu
        Bitmap graphics (SDSC Synu image file)
 .sys
        Datafile (SYGRAPH - SYSTAT - SPSS/PC)
 .sys
        System file - device driver or hardware configuration info (DOS)
 .syw
        Graphics symbols (Harvard Graphics Win)
 .syw
        Yamaha SY-85/SY-99 Wave File


t

 .t
       Tads source
 .t
       Tape Archive without compression (tar)
 .t
       Tester symbol table (ReaGeniX code generator)
 .t
       Unformatted manual page (Roff/nroff/troff/groff)
 .t44
       Temporary file for Sort or Index (dBASE IV)
 .t64
       Commodore 64 emulator tape file (C64S emulator)
 .t65
       Template (PageMaker)
 .taac
       Bitmap graphics (Sun TAAC Image File Format)
 .tab
       Colour lookup table (CMYK image) (Stork format)
 .tag
       Query tag name (DataFlex)
 .tah
       Help file (Turbo Assembler)
 .tal
       Text illustration (TypeAlign)
 .talk
       Text to speech
 .tap
       Tape file (ZX Spectrum emulator by g.a.lunter)
 .tar
       Compressed file archive (tar)
 .targa
       Bitmap graphics (Truevision Targa format)
 .taz
       Compressed file.tar.Z archive (ascii) (tar and compress)
 .tb1
       Font file (Borland Turbo C)
 .tb2
       Font file (Borland Turbo C)
 .tbf
       Fax (Imavox TurboFax)
 .tbk
       Memo backup (dBASE IV - FoxPro)
 .tbk
       Toolbook (Asymetrix ToolBook)
 .tbl
       Dynamic Link library
 .tbl
       Table
 .tbr
       Custom toolbar (Norton Desktop)
 .tbs
       Text elements (Textbausteine) (German MS Word)
 .tbx
       Table (Project Scheduler 4)
 .tc
       Configuration (Turbo C - Borland C++)
 .tc
       Termcap
 .tch
       Help file (Turbo C - Borland C++)
 .tcl
       Tcl (Tool Command Language) script source code
 .tco
       T9000 object modules
 .tcw
       Drawing (TurboCAD for Windows)
 .td
       Configuration file (Turbo Debugger for DOS)
 .td0
       Disk image (compressed diskette in a file) (Teledisk)
 .td2
       Configuration file (Turbo Debugger for Win32)
 .tdb
       Database (TACT)
 .tddd
       Imagine Object File Format
 .tdf
       Font (TheDraw)
 .tdf
       Typeface definition file (Speedo)
 .tdh
       Help file (Turbo Debugger)
 .tdi
       Animation (TDI image file)
 .tdk
       Keystroke recording file (Turbo Debugger)
 .tdr
       Contens of Arvid tape
 .tds
       Symbol table (Turbo Debugger)
 .tdw
       Configuration file (Turbo Debugger for Windows)
 .tdw
       Debugger symbol table (Borland C++ Builder)
 .tef
       Fax (Relisys TEFAX)
 .tel
       Host file (Telnet)
 .tem
       Input template (IconAuthor)
 .tem
       Turbo Editor Macro Language script (Borland C++)
 .tet
       Tetris results (DN)
 .tex
       Datasheet (Idealist)
 .tex
       Text document (TeX Device Independent File Format) (Scientific Word)
 .tex
       Texture file (possible graphics)
 .text
       Text file
 .tf
       Configuration (Turbo Profiler)
 .tf
       MUD client macro (TinyFugue)
 .tfa
       Area file (Turbo Profiler)
 .tfc
       Catalogue file (Tobi's Floppy Cataloguer)
 .tfh
       Help file (Turbo Profiler)
 .tfm
       Tagged font metric file (Intellifont - TeX)
 .tfs
       Statistical information (Turbo Profiler)
 .tg
       Technical Guidance (NRC Inspection Manual)
 .tg1
       Project file (On Target)
 .tga
       Bitmap graphics (Truevision Targa format)
 .tgz
       Compressed file archive.tar.gz (tar and GNUzip)
 .theme
       Desktop theme (Windows 95)
 .thm
       Bitmap graphics (Picture Publisher - PhotoMagic Thumbnail)
 .thn
       Thumbnail (Graphics Workshop for Windows)
 .thor
       Database description (THOR database)
 .ths
       Thesaurus dictionary (WordPerfect for Win)
 .ti
       Temporary Instruction (NRC Inspection Manual)
 .tic
       FTN special file with assotiated file description (ALLFIX)
 .tif
       Bitmap graphics (Tagged Image File Format) (PageMaker - CorelDraw)
 .tiff
       Bitmap graphics (Tagged Image File Format) (PageMaker - CorelDraw)
 .tig
       Tiger file (US government distributed maps)
 .til
       Fuzzy logic knowledge base (Togai InfraLogic Fuzzy-C Compiler)
 .tis
       Tile set (MahJongg 3.0)
 .tjl
       Backup file (VAXTPU editor)
 .tlb
       OLE Type library (Visual C++)
 .tlb
       Reference table (Bubble Chamber)
 .tlb
       Text library (VAX)
 .tlc
       Compiled Tool Command Language source code (Geoworks Swat)
 .tld
       Disk Image (Teledisk)
 .tlp
       Project (TimeLine)
 .tm
       Bitmap graphics (EOSAT's Landsat Thematic Mapper data file)
 .tmf
       Tagged Font Metric file (WordPerfect for Win)
 .tmo
       Ztg global optimizer default output file (Zortech C++)
 .tmp
       Temporary file
 .tms
       Script (Telemate)
 .tms
       TeleMate compiled script (TeleMate)
 .tny
       Bitmap graphics (Atari TINY Bitmap)
 .toc
       Table Of Contents (index file)
 .tok
       External tokens (Borland C++ 4.x)
 .tos
       Self-extracting file archive (Atari ST)
 .tp
       Configuration (Turbo Pascal)
 .tp
       Session-state file (Turbo Profiler)
 .tp3
       Template (Harvard Graphics 3.0)
 .tpb
       Downloadable PCL Soft font file backup (HiJaak)
 .tpf
       Downloadable PCL Soft font file (HiJaak)
 .tph
       Help file (Turbo Pascal)
 .tpl
       Resident units library (Turbo Pascal)
 .tpl
       Template (Harvard Graphics - GoldEd -ITrack)
 .tpp
       Protected Mode Units (Borland Pascal 7.0)
 .tpu
       Command file (VAXTPU editor)
 .tpu
       Pascal Unit (DOS library) (Borland Pascal)
 .tpw
       Pascal Unit (Windows library) (Borland Pascal)
 .tpw
       Session-state file (Turbo Profiler for Windows)
 .tpz
       Compressed file archive.tar.gz (tar and GNUzip)
 .tr
       Session-state settings (Turbo Debugger for DOS)
 .tr
       Unformatted manual page (Roff/nroff/troff/groff)
 .tr2
       Session-state settings (Turbo Debugger for Win32)
 .trc
       Debug support file (Power CTrace)
 .tre
       Directory tree file (PC-Tools)
 .trif
       Bitmap graphics (Tiled Raster Interchange Format)
 .trk
       Track (i.e. video sequence) used by many games
 .trm
       Terminal settings (Windows 3.x)
 .trn
       Translation support file (Quattro - Clarion)
 .trs
       Executable file (Micrografx)
 .tru
       True Basic language source code file
 .trw
       Session-state settings (Turbo Debugger for Windows)
 .tsm
       Manual (Turbo Assembler for OS/2)
 .tsq
       ODBC script
 .tst
       Printer test file (WordPerfect for Win)
 .tsv
       Tab Separated Values
 .ttf
       Truetype Font (font file)
 .tud
       Document (The Ultimate Draw)
 .tut
       Tutorial
 .tv
       Table view settings (Paradox)
 .tv1
       Overflow file above insert point in Doc 1 (WordPerfect for Win)
 .tv2
       Overflow file above insert point in Doc 2 (WordPerfect for Win)
 .tv3
       Overflow file above insert point in Doc 3 (WordPerfect for Win)
 .tv4
       Overflow file above insert point in Doc 4 (WordPerfect for Win)
 .tv5
       Overflow file above insert point in Doc 5 (WordPerfect for Win)
 .tv6
       Overflow file above insert point in Doc 6 (WordPerfect for Win)
 .tv7
       Overflow file above insert point in Doc 7 (WordPerfect for Win)
 .tv8
       Overflow file above insert point in Doc 8 (WordPerfect for Win)
 .tv9
       Overflow file above insert point in Doc 9 (WordPerfect for Win)
 .tvf
       Table view settings (dBASE)
 .twf
       Data (TabWorks)
 .tww
       Tagwrite Template
 .tx8
       8-bit ASCII text
 .txf
       Compressed file archive.tar.f (tar and Freeze)
 .txi
       Support file (TeX)
 .txt
       Plain text (ASCII or ISO Latin 1 format)
 .txw
       Yamaha TX-16W Wave File (Convert (c) Villena)
 .tym
       Time Stamp (PageMaker 4)
 .tz
       Compressed file archive.tar.Z (tar and compress)
 .tzb
       Compressed file archive.tar.Z.btoa (tar - compress - btoa)


u

 .u
       Bitmap graphics (subsampled raw YUV file)
 .u4a
       UnInstaller archive
 .u8
       Sample
 .ub
       Music file (unsigned byte)
 .uc2
       Compressed file archive (UltraCompressor II)
 .ucd
       Use case diagram (Prosa/OM)
 .ucn
       New compressed file archive (UltraCompressor II)
 .udf
       Filter (Photostyler)
 .udf
       Uniqueness Database File (Windows NT)
 .ue2
       Encrypted file archive (UltraCompressor II)
 .ufa
       Compressed file archive (UFA)
 .ufo
       Ulead File for Objects (Ulead PhotoImpact)
 .uhs
       Universal Hint System (binary file)
 .ui
       Espire language source code file (Geoworks UI Compiler)
 .ui
       User interface (Sprint)
 .uif
       Long prompts for windows (WordPerfect for Win)
 .uih
       Espire header file (Geoworks UI Compiler)
 .uil
       Bitmap graphics (Motif UIL icon file)
 .ul
       Music file (Ulaw)
 .uld
       Uploaded file information (Procomm Plus)
 .ult
       Music (UltraTracker)
 .umb
       Backup file (MemMaker)
 .und
       Undefined symbols (A86)
 .uni
       Datafile (Forecast Pro)
 .uni
       Music (UniMOD - MikMOD)
 .unv
       SDRC I-DEAS file
 .unx
       Text file containing UNIX specific info
 .upd
       Update info
 .upf
       Bitmap graphics (Universal Picture Format)
 .upo
       Compiled update data (dBASE)
 .uri
       List of Uniform Resource Identifiers (WWW)
 .uris
       List of Uniform Resource Identifiers (WWW)
 .url
       Internet shortcut (Universal Resource Locator)
 .urt
       Bitmap graphics (Utah Run-Length Encoded image file)
 .use
       Log file
 .usp
       Printer font with US Ascii extended character set (PageMaker)
 .usr
       User database (Procomm Plus - Turbo C++ tour)
 .ustar
       Compressed file archive (POSIX tar)
 .uu
       Encoded file archive (ascii) (uudecode - uuencode)
 .uud
       Encoded file archive (ascii) (uuencode)
 .uue
       Encoded file archive (ascii) (uuencode)
 .uw
       Music file (unsigned word)
 .uwf
       Music file (UltraTracker WaveSample)


v

 .v
      Bitmap graphics (subsampled raw YUV file)
 .v
      Consistency check support file (ReaGeniX code generator)
 .v
      Main input file for an image (Vivid 2.0)
 .val
      Validity checks and referential integrity (Paradox for Windows)
 .val
      Values list object file (dBASE Application Generator)
 .van
      Animation (VistaPro)
 .vap
      Value Added Process (NetWare 2.xx)
 .var
      Variable file (IconAuthor)
 .vbp
      Visual Basic Project
 .vbr
      Visual Basic Custom Control file (Visual Basic)
 .vbx
      Visual Basic eXtension (custom control)
 .vbz
      Visual Basic Setup Wizard Template (Setup Wizard)
 .vc
      Include file with color definitions (Vivid 2.0)
 .vc
      Spreadsheet (VisiCalc)
 .vca
      Visual Clip Art
 .vcf
      Vevi Configuration File (WorldToolKit objects)
 .vcr
      VCR driver (Arvid)
 .vcs
      Calendar data (Netscape Calendar)
 .vcw
      Visual workbench information (MS Visual C++)
 .vcx
      Spreadsheet (VisiCalc Advanced)
 .vda
      Bitmap graphics (Truevision Targa format)
 .vda
      Graphics (VDA-FS surface data)
 .vdi
      Bitmap graphics (Digital Research GEM VDI file)
 .vdo
      Video image (Story Board)
 .vdr
      Drawing (ComputerEasy Draw)
 .veh
      Vector data (SPANS VEH/VEC format)
 .vew
      GroupWise for Windows
 .vew
      View file (Clipper 5 - Lotus Approach)
 .vfa
      Database file (FontLab)
 .vff
      Bitmap graphics (DESR VFF Greyscale Image)
 .vff
      Bitmap graphics (Sun TAAC Image File Format)
 .vfm
      Ventura Font Metrics file (Ventura Publisher)
 .vfm
      Voting Form (Voter)
 .vfn
      Voting Form for Customers (Voter)
 .vga
      Bitmap graphics (OS/2 bitmap)
 .vga
      Vga display font
 .vgd
      Vga display driver (Generic CADD)
 .vgr
      Graphics (Ventura Publisher)
 .vi
      Bitmap graphics (Jovian Logic VI video capture board)
 .vi
      Script (Watcom Vi editor)
 .vic
      Graphics (VICAR - Video Image Communication and Retrieval)
 .vicar
      Graphics (VICAR - Video Image Communication and Retrieval)
 .vid
      Bitmap graphics (YUV12C M-Motion Frame Buffer file)
 .vid
      Screen device driver (MSDOS - Word)
 .vif
      Bitmap graphics (1bit CCITT Group 4) (Verity Image Format) (Topic)
 .vif
      Bitmap graphics (Khoros Visualization Image File Format)
 .viff
      Bitmap graphics (Khoros Visualization Image File Format)
 .vik
      Graphics (Viking)
 .vir
      Virus or infected file
 .vis
      Graphics (Vista)
 .vit
      Bitmap graphics (VITec file)
 .vlb
      Corel Ventura Library
 .vlm
      Virtual Loadable Module (Netware)
 .vm
      Virtual Memory file (or localization file) (Geoworks)
 .vmc
      Virtual memory configuration (DOS/4GW PM 32X DOS Extender)
 .vmf
      Font characteristics (Ventura Publisher)
 .vms
      Text file containing VMS specific info
 .vo
      Include file with object definition (Vivid 2.0)
 .voc
      Sound (Creative Lab's Sound File) (PlayVoc)
 .vof
      Object folder (VZ Programmer)
 .vort
      Bitmap graphics (Very Ordinary Rendering Toolkit)
 .vp
      Publication (Ventura Publisher)
 .vp
      Video posting (3D Studio)
 .vpf
      Vector Product Format
 .vpg
      Graphics (VPGraphics)
 .vph
      Virtual Pascal Help (VP/OS2)
 .vpi
      Virtual Pascal Unit (VP/OS2)
 .vpr
      Resource (Visual Prolog)
 .vrm
      Overlay file (QuattroPro)
 .vrm
      Virtual Reality Modeling Language (WWW)
 .vrm
      Visual Rexx language source code file (Watcom VRexx)
 .vrml
      Virtual Reality Modeling Language (WWW)
 .vrp
      Project (WATCOM VXRexx)
 .vrs
      Video Resource (device driver) (WordPerfect)
 .vrt
      Virtual world (WWW)
 .vs
      Include file with surface definition (Vivid 2.0)
 .vsd
      Drawing (Visio)
 .vsm
      Simulation model (VisSim)
 .vsp
      Sprite (SPX)
 .vss
      Smartshapes file (Visio)
 .vst
      Bitmap graphics (Truevision Vista)
 .vst
      Template (Visio)
 .vsw
      Data (Visio Workspace)
 .vue
      Animation (3D Studio)
 .vue
      View (dBASE IV - FoxPro)
 .vw
      Text file (Volkswriter)
 .vwr
      File viewer file (PC Tools)
 .vxd
      Virtual device driver (MS Windows)


w

 .w
         Word chart file (APPLAUSE)
 .w30
         Printer font (AST TurboLaser) (Ventura Publisher)
 .w31
         Startup file (Windows 3.1)
 .w44
         Temporary file for Sort or Index (dBASE)
 .w51
         Document (WordPerfect 5.1)
 .w60
         Document (WordPerfect 6.0)
 .w61
         Document (WordPerfect 6.1)
 .w95
         Microsoft Windows95 related file
 .wad
         War Allocation Daemon (Doom - Doom2)
 .was
         Script file (source code) (ProComm)
 .wav
         Sound (RIFF WAVE waveform audio format) (Media Player)
 .wax
         Compiled script (ProComm)
 .wb1
         Notebook (Quattro Pro)
 .wb2
         Spreadsheet (Quattro Pro)
 .wbf
         Windows Batch File (Catch)
 .wbk
         Auto-backup (MS Word)
 .wbk
         Document/workbook (WordPerfect for Win)
 .wbl
         Upload file (Argo WebLoad II)
 .wbt
         Batch file (WilsonWare WinBatch)
 .wcd
         Macro token list (WordPerfect for Win)
 .wch
         Macro facility file (WordPerfect)
 .wcm
         Data transmission file (MS Works)
 .wcm
         Macro (WordPerfect for Win)
 .wcp
         Product information description (WordPerfect for Win)
 .wd
         Data file (InfoSelect)
 .wdb
         Database (MS Works)
 .web
         Web document (Corel Xara)
 .weboogl
         Web Object Oriented Graphics Library
 .wfm
         Form object (dBASE Form Designer)
 .wfn
         Windows 3.0 font file (CorelDraw)
 .wfx
         Data file (Winfax)
 .wg1
         Worksheet (Lotus 1-2-3/G)
 .wg2
         Worksheet (Lotus 1-2-3 for OS/2)
 .wgp
         Game data (Wild Board Games)
 .whip
         Bitmap graphics (WHIP file)
 .wic
         Garbage, fake compressed data. Your files are in WINFILE.DLL
 .wid
         Width table (Ventura Publisher)
 .wil
         Data (WinImage)
 .win
         Window file (FoxPro - dBASE)
 .wins
         Makefile for WINS platform (EPOC)
 .wiz
         Page wizard (MS Publisher - MS Word)
 .wiz
         Wizard (MS Word)
 .wk1
         Spreadsheet (Lotus 123 version 2.x - Symphony 1.1+)
 .wk3
         Spreadsheet (Lotus 123 version 3.x)
 .wk4
         Spreadsheet (Lotus 123 version 3.4)
 .wkb
         Document (WordPerfect for Win)
 .wke
         Spreadsheet (Lotus 123 educational version)
 .wki
         Spreadsheet format (Lotus 123 2.x)
 .wkq
         Spreadsheet (Quattro)
 .wks
         Document (Microsoft Works)
 .wks
         Spreadsheet (Lotus 123 version 1A - Symphony 1.0 - MS Works)
 .wks
         Workspace (Xlisp)
 .wkz
         Spreadsheet (Wingz)
 .wlf
         Upload file (Argo WebLoad I)
 .wlk
         Graphics (Virtus Walkthrough)
 .wll
         Add-in (MS Word)
 .wmc
         Backup of startup files (MathCad)
 .wmc
         Macro file (WordPerfect for Win)
 .wmc
         Text file (WordMARC)
 .wmf
         Vector graphics (Windows MetaFile format)
 .wml
         Wireless Markup Language document (WAP)
 .wmp
         Graphics (Windows Magic Icon Palette)
 .wn
         Text document (NeXT WriteNow)
 .wnf
         Outline font description (CorelDraw native format)
 .woa
         Swap file (Windows 3.x)
 .wob
         Object file (RIO Designer Pro)
 .woc
         Organization (Windows OrgChart)
 .wow
         Music (8 channels) (Grave Mod Player)
 .wp
         Text document (WordPerfect 4.2)
 .wp4
         text document (WordPerfect 4.x)
 .wp5
         Text document (WordPerfect 5.x)
 .wp6
         Text document (WordPerfect 6.x)
 .wpd
         Text document (WordPerfect 6.0 - PFS:WindowWorks)
 .wpd
         Windows printer driver
 .wpf
         Fax (WorldPort)
 .wpf
         Form (WordPerfect)
 .wpg
         Bitmap graphics (WordPerfect Graphics Format)
 .wpg
         Vector graphics (WordPerfect Graphics Format)
 .wpj
         Project (Watcom C/C++)
 .wpk
         Macros (WordPerfect for Win)
 .wpm
         Macros (WordPerfect)
 .wpm
         Text document (WordPerfect for Mac)
 .wps
         Text document (MS Works)
 .wpt
         Template (WordPerfect)
 .wpw
         Document (Novel PerfectWorks)
 .wq!
         Compressed spreadsheet (Quattro Pro)
 .wq1
         Spreadsheet (Quattro Pro DOS)
 .wq2
         Spreadsheet (Quattro Pro 5 DOS)
 .wr1
         Spreadsheet (Symphony 1.1 - 1.2 - 2)
 .wrd
         Template (Charisma)
 .wrd
         Text document (Psion Series 3)
 .wri
         Text document (Windows Write)
 .wrk
         Spreadsheet (Symphony 1.0)
 .wrl
         3D virtual reality object (VRML worlds) (Cosmo Player)
 .wrp
         Compressed Amiga file archive (Warp)
 .wrs
         Windows Resource eg. printer driver (WordPerfect for Win)
 .wrz
         VRML worlds (Cosmo Player)
 .ws
         APL Worksheet
 .ws
         Text document (WordStar 5.0-6.0)
 .ws1
         Text document (WordStar for Windows 1)
 .ws2
         Text document (WordStar 2000 - WordStar for Windows 2)
 .ws3
         Text document (WordStar for Windows 3)
 .ws4
         Text document (WordStar for Windows 4)
 .ws5
         Text document (WordStar for Windows 5)
 .ws6
         Text document (WordStar for Windows 6)
 .ws7
         Text document (WordStar for Windows 7)
 .wsc
         Scene file (RIO Designer Pro)
 .wsd
         Document (WordStar)
 .wsp
         Workspace (Fortran PowerStation)
 .wsq
         Wavelet-packet Scalar Quantization Format
 .wsrc
         x-wais source
 .wst
         Text document (WordStar)
 .wtk
         URL address of person to talk to (WinTalk)
 .wtx
         Text document
 .wve
         Sound (8kHz) (Psion Series 3 palmtop)
 .wvl
         Bitmap graphics (Wavelet Compressed Bitmap)
 .wwb
         Button bar for document window (WordPerfect for Win)
 .wwk
         Keyboard layout (WordPerfect for Win)
 .wxp
         Document (EXP for Windows)


x

 .x
      Archive (X1)
 .x
      Bitmap graphics (24bit) (AVS X image file)
 .x
      Lex language source code file
 .x
      Self-extracting archive (Alysis SuperDisk)
 .x
      X-file animation (Direct3D) (DeepV2)
 .x01
      Secondary index (Paradox)
 .x02
      Secondary index (Paradox)
 .x03
      Secondary index (Paradox)
 .x04
      Secondary index (Paradox)
 .x05
      Secondary index (Paradox)
 .x06
      Secondary index (Paradox)
 .x07
      Secondary index (Paradox)
 .x08
      Secondary index (Paradox)
 .x09
      Secondary index (Paradox)
 .x10
      Bitmap graphics (X Window dump)
 .x11
      Bitmap graphics (X Window dump)
 .x3d
      x3d and xdart Formats
 .xar
      Drawing (Corel Xara)
 .xbm
      Bitmap graphics (1bit text) (X Window BitMap)
 .xc
      Bitmap graphics (Constant image of X server screen)
 .xck
      Extended crack file (usually text)
 .xcl
      Script file (Xtree for Win)
 .xdf
      Extended disk format image (OS/2 xdfcopy.exe)
 .xfn
      Printer font (Xerox 4045) (Ventura Publisher)
 .xfr
      Bitmap editor font file (Ventura Publisher)
 .xft
      24 pin printer font (ChiWriter)
 .xgl
      Graphics language file (MegaBitz)
 .xgz
      Vector drawing (MegaBitz)
 .xi
      Instrument file (Fastracker 2.0)
 .xif
      Graphics (eXtended Image File Format)
 .xim
      Bitmap graphics (X11 Xim Toolkit file)
 .xl
      Spreadsheet (Excel)
 .xla
      Add-in macro sheet (MS Excel)
 .xla
      Xlib Archive (Xlib graphics library)
 .xlb
      Worksheet (MS Excel)
 .xlc
      Chart (MS Excel)
 .xld
      Dialog sheet (MS Excel)
 .xlk
      Backup (MS Excel)
 .xll
      XLL add-in (MS Excel)
 .xlm
      Macro (MS Excel)
 .xls
      Spreadsheet (MS Excel)
 .xlt
      Template (MS Excel)
 .xlt
      Translation table (Lotus 1-2-3 - Symphony - Procomm Plus)
 .xlv
      VBA Module (MS Excel)
 .xlw
      Workspace (MS Excel)
 .xm
      Music (FastTracker - Cubic Player)
 .xmi
      Compressed eXtended MIdi music
 .xml
      XML document (Extensible Markup Language)
 .xmz
      XGL movie (MegaView)
 .xnf
      Standard Network File form
 .xnk
      Shortcut (MS Exchange)
 .xof
      RenderMorphics
 .xos
      Bitmap graphics (Xaos Tools image file)
 .xpm
      Bitmap graphics (8bit text) (X11 pixmap file)
 .xqt
      Executable file (Waffle)
 .xqt
      Macro sheet (SuperCalc)
 .xr1
      Game data (Epic MegaGames Xargon)
 .xref
      Cross reference (AIX as)
 .xrf
      Cross-reference file
 .xsc
      XML schema
 .xt
      Music track (FastTracker)
 .xtb
      External translation table (LocoScript)
 .xtp
      Overlay (XTreeGold)
 .xv
      Bitmap graphics (Khoros Visualization Image File Format)
 .xwd
      Bitmap graphics (X Window Dump screen window image format)
 .xwk
      Keyboard mapping (Crosstalk)
 .xwp
      Session (Crosstalk)
 .xwp
      Text document (Xerox Writer)
 .xx
      Encoded file archive (ascii) (xxdecode - xxencode)
 .xxe
      Encoded file archive (ascii) (xxencode)
 .xy
      Text document (XY Write)
 .xy3
      Text document (XYWrite III)
 .xy4
      Text document (XYWrite IV)
 .xyp
      Text document (XYWrite III Plus)
 .xyw
      Text document (XYWrite for Windows 4.0)


y

 .y
      Bitmap graphics (subsampled raw YUV file)
 .y
      Compressed Amiga file archive (Yabba)
 .y
      Grammar file (Yacc)
 .y01
      Secondary index (Paradox)
 .y02
      Secondary index (Paradox)
 .y03
      Secondary index (Paradox)
 .y04
      Secondary index (Paradox)
 .y05
      Secondary index (Paradox)
 .y06
      Secondary index (Paradox)
 .y07
      Secondary index (Paradox)
 .y08
      Secondary index (Paradox)
 .y09
      Secondary index (Paradox)
 .yal
      Clipart library (Arts & Letters)
 .ybk
      Yearbook (Microsoft Encarta)
 .ybm
      Bitmap graphics (Face file)
 .yc
      Archive (YACC)
 .yif
      Graphics (color with lookup table)
 .yuv
      Bitmap graphics (Abekas YUV file or CCIR 601 1:1:1 file)
 .yuv3
      Bitmap graphics (CCIR 601 2:1:1 files)
 .yz
      Compressed file archive (YAC)


z

 .z
      Compressed file archive.z (binary) (Unix SysV pack)
 .z3
      Infocom game module
 .z80
      Snapshot (ZX Spectrum emulator by g.a.lunter)
 .zad
      Digitized voice file (ZFax)
 .zdg
      Compressed ZiffNet text document (Zview)
 .zeiss
      Bitmap graphics (Zeiss CSLM file)
 .zer
      Data file (Zerberus)
 .zfd
      Zeroadic functions (ABC programming language)
 .zgm
      Graphics (Zenographics)
 .zinc
      Bitmap graphics (Zinc Interface Library icon file)
 .zip
      Compressed file archive (InfoZIP - PKZip - WinZip)
 .zom
      Compressed Amiga file archive (Zoom)
 .zoo
      Compressed file archive (Zoo)
 .zpd
      Zeroadic predicates (ABC programming language)
 .zrp
      Rapid simulation package (Rapid)
 .zts
      Script (Z-Term)
 .zvd
      Zyxel Voicefile (Z-Fax)
 .zw
      Chinese text
 .zze
      Encoded file archive (ascii)


~

 .~$~
      Temporary file (1st Reader)
 .~ap
      Old AppExpert project database (Borland C++ 4.x)
 .~de
      Project backup (Borland C++ 4.x)
 .~mn
      Menu backup (Norton Commander)


?

 .?$?
      Temporary file (1st Reader)