Glossary
D data bits How many bits of information are included in each byte sent (usually eight).
DB-15 Standard display connector.
DB-25 Standard parallel or serial connector. See parallel port or serial port.
DB-9 Standard nine-pin serial connector. See serial port.
DDE Dynamic Data Exchange, a way for Windows programs to exchange information.
DDE action DDE command that defines how data moves to or from files of a specified type.
default The information or mode that a program uses unless you specify otherwise.
default e-mail program E-mail program that runs when you right-click a file and choose Send To | Mail Recipient or use another command to send an e-mail. Appears on the left side of the Start menu.
default printer Printer to which print jobs are sent unless you specify otherwise.
default Web browser Browser that Windows runs when you open a Web page by clicking a shortcut to a Web page or the filename of an HTML file. Appears on the left side of the Start menu.
deferred printing Queuing print jobs on a computer without a printer to be printed when you connect a printer to your computer later.
defragmenting Moving the contents of files around on your hard disk so that each file is stored as one big chunk, speeding up access to the file.
desktop Work area on your screen on which you see your programs. The desktop can contain windows, icons, and the taskbar.
desktop theme Set of desktop background, cursor, font, and color settings to dress up your desktop.
Desktop toolbar Toolbar that can appear on the taskbar, containing a button for each icon on the desktop.
Details view Way of representing the contents of a folder, in which items are listed with a tiny icon, the filename, the file's size, the file's type, when it was last modified, and its attributes.
device driver See driver.
Device Manager Windows program that lists all the devices that make up your computer and lets you see and modify their configuration.
DHCP Dynamic Host Configuration Protocol, a system that assigns IP addresses for a LAN.
DHCP server Computer running DHCP software that assigns IP addresses to other computers on a network. Internet Connection Sharing includes a DHCP server.
dialing location Location from which you place phone calls. You can tell Windows the area code and other information about the phone line at that location.
dialog box Type of window that allows you to change settings or give commands in a program. Most dialog boxes include OK and Cancel buttons.
dial-up modem Device that connects to your computer to a regular dial-up phone line.
dial-up connection Network connection that uses a dial-up telephone line to connect to the Internet or to another computer.
digital camera Device that digitizes video input (through the lens of the camera) for use by your computer.
digital ID File containing encryption and digital identification information that you can use to digitally sign or encrypt e-mail and newsgroup messages in Outlook Express. See also certificate.
digital signature Information added to the end of an e-mail message to prove who sent it.
digitally signed message E-mail message that has been encrypted with a digital ID to prove who sent it.
direct network connection Connecting two computers with a serial cable to allow file or printing sharing. Called Direct Cable Connection (DCC) in previous versions of Windows.
direct memory access See DMA.
directory See folder.
directory server Computer that stores the addresses of people who use NetMeeting.
directory service Searchable listing of names, e-mail addresses, and other information about people.
DirectX Enhanced video system built into Windows.
Disk Cleanup Windows utility that deletes unneeded temporary files to free up space on your disk.
disk controller Adapter card that connects a hard disk to your computer.
Disk Defragmenter Disk cleanup program that stores files more efficiently on your disk.
Disk Management Program that displays information about disks and partitions, and enables you to change their configuration.
display properties Properties of your display and your Windows desktop.
distribution file See installation file.
DLL file Dynamic link library file, an executable file with the file extension .dll invoked from a running program.
DMA Direct memory access, a system board facility used by a few medium-speed devices to communicate with the CPU.
DNS or DNS server See domain name server.
DOC file Document file, with the file extension .doc. DOC files are usually (but not always) created by Microsoft Word or a compatible program.
docking station Hardware device into which you plug a laptop to provide connections to a monitor, keyboard, mouse, local area network, and/or additional PC Card slots.
domain On a LAN, a group of computers administered by one server. On the Internet, a two-part name used for one or more Internet hosts (for example, gurus.com).
domain-based network Server-based network, hosted on a Windows .NET Server, 2000 Server, or NT system. Domains provide network security that is controlled by the server, rather than by each computer on the network.
domain name Alphanumeric name of a computer or group of computers on the Internet; for example, gurus.com.
domain name server (DNS) Computer on the Internet that translates between Internet domain names and numeric IP addresses. You can specify two DNSs for an Internet connection: a primary server and a secondary server.
DOS Disk Operating System, the operating system on which Windows runs. Sometimes called MS-DOS.
DOS initialization file One of the files that Windows reads when starting up a DOS program or Command Prompt window: Autoexec.nt and Config.nt.
DOS name Filename used by DOS programs and early Windows programs, limited to an eight-character name and a three-character extension.
DOS program Program written to work with the DOS operating system.
DOS prompt Prompt that DOS displays when it is waiting for you to type a command.
DOS Virtual Machine (VM) Emulation program that allows DOS programs to run under Windows XP.
DOS window See Command Prompt window.
double-click speed Time period within which the two clicks of a double-click must occur, with no intervening mouse motion.
double-click style Desktop mode in which clicking an icon or filename twice runs the program or opens the file. To select the icon or filename without running or opening it, click it once.
download Transfer a file from the Internet, other network, or mainframe to a PC.
downloaded object security Security for information you download from the Internet.
Dr. Watson Windows utility that takes a snapshot of the system's state when a program fails.
drag-and-drop Method of moving or copying information from one file to another, or to another location in the same file.
drive letter Letter that identifies a disk drive, other storage device, or a partition of a drive.
driver Or device driver. Software that allows Windows to communicate with a device, such as a display or printer.
drop-down menu Menu that appears when you click a command on a menu bar.
DSL Digital Subscriber Line (or Loop), an all-digital telephone line that uses the "last mile" of copper line between your computer and the central phone company offices. Actually a family of types of lines, including ADSL, HDSL, SDSL, and others.
DSL modem Device that connects a computer (usually via a network interface card) to a DSL phone line.
DSP Digital signal processor, a specialized computer chip for compressing video signals.
dual-boot installation Computer that can be started in either of two operating systems; for example, Windows XP and Windows 98, or Windows XP and Linux.
DVD Digital versatile disk or digital video disk, a digital disk that can contain video material.
DWORD Type of Registry entry that contains a numeric value (specifically, a four-byte hexidecimal number).
dynamic addressing System that assigns an address to a computer when the computer connects to the network. Each time the computer connects, it may get a different address. Windows supports to forms of dynamic addressing, Automatic private IP addressing and DHCP.
Dynamic Data Exchange See DDE.
dynamic disk Disk in which the volumes can be managed dynamically (on the fly).
Dynamic Host Configuration Protocol See DHCP.
dynamic link library file See DLL file.
dynamic volume See dynamic disk.
