TAB or tablature is a method of writing down music played on guitar or bass.
Instead of using symbols like in standard musical notation, it uses ordinary
ASCII characters and numbers, making it ideal for places like the internet
where anybody with any computer can link up, copy a TAB file, and read it.

TAB will tell you what notes to play - it will tell you which string to hit
and which fret to fret it at.

TAB will tell you where hammer-ons, pull-offs, bends, slides, harmonics and 
vibrato are used. 

TAB will tell you what tuning the piece is in.  If this isn't given 
explicitly, assume normal tuning.  TAB should also give you information
on use of capos etc.

TAB will give you an indication of the ryhthm of the piece - i.e it will tell
you which are the long notes and which are the short notes.  

However it will not tell you exactly how long or how short they are.

This leads me on to ...

TAB will (usually) not tell you the note lengths of the notes - so in most 
cases you will have to listen to the song yourself, with the TAB in front
of you to work out the ryhthm of the notes.

TAB will not tell you which fingers you use to fret which note.

TAB will (usually) not tell you anything about picking and strumming -
you will have to decide for yourself where to use upstrokes/downstrokes
and so on.

TAB is simple to read, and should be simple to write if you want to submit
a song you have worked out yourself.  The idea is this :

You start out with 6 lines (or four for bass). These correspond to the strings
of the instrument.  The top line is the highest pitch string, and the bottom 
line is the lowest pitch string.  Below is a blank bit of TAB with the string
names at the left.


E----------------------------------------------------------------
B----------------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------


Numbers are written on the lines to show you where to fret the string
with the left hand. If a zero appears , this means play the open string.
Like standard musical notation, you read from left to right to find
out what order to play the notes.  The following piece of TAB would mean
play the sequence of notes (E F F# G G# A) on the bottom E string by
moving up a fret at a time, starting with the open string.


E----------------------------------------------------------------
B----------------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E---0--1--2--3--4--5---------------------------------------------


OK so far ?

Here we have notes being played one at a time. If two or more notes
are to be played together, they are written on top of one another,
again just like standard notation.

In the next example we have a G bar chord.

E----3------------------------------------------------------------
B----3------------------------------------------------------------
G----4------------------------------------------------------------
D----5------------------------------------------------------------
A----5------------------------------------------------------------
E----3------------------------------------------------------------


So this means play all these notes together as a chord.

You might see the same chord written like this :

E--------3--------------------------------------------------------
B-------3---------------------------------------------------------
G------4----------------------------------------------------------
D-----5-----------------------------------------------------------
A----5------------------------------------------------------------
E---3-------------------------------------------------------------


Which would mean strum the same shape starting at the bottom string, so
that each string is hit slightly later than the last string, but all notes
will ring together. Below is am example of the same shape again, but now
the gaps between the notes are bigger - so you would probably pick the 
strings separately instead of slowly strumming the shape.


E------------------3----------------------------------------------
B---------------3-----3--------------------------------------------
G------------4-----------4-----------------------------------------
D---------5-----------------5--------------------------------------
A------5-----------------------5----------------------------------
E---3-----------------------------3--------------------------------


You might ask - How do I know how fast or slow to play this ?
                Are all the notes supposed to be the same length ?


This is where TAB differs from standard notation. Most often TAB 
will *not* give you any information on the note lengths.  It is usually
left up to you to listen to the song to pick up the rhythm.

However - don't despair. TAB should give you some indications of
timing.  In the example above all the notes are evenly spaced so you
can reasonably assume that the notes are the same length (maybe all
eighth notes or quavers) but this may not always be true - it depends on
who wrote the TAB.

As a general rule, the spacing of the notes on the TAB should tell you
which notes are the long ones, and which are the short and fast ones, but
obviously it won't tell you if a note is a triplet or anything like
that.  Again, this will depend strongly on the person who wrote the
TAB.

As an example, here are the first few notes of the American National
Anthem in TAB.  You should see fairly clearly that the different spacing
corresponds to the different note lengths.

E-----------------------0--------4--2-0--------------------------
B---0--------------0---------------------------------0-----------
G------1------1----------------------------1----3----------------
D--------2-------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------


Obviously it will be a lot easier to play the TAB for a song you
know well than for a song you've never heard of because you will
already be familiar with the ryhthms of the familiar song.

So far I've looked at what notes to play : which string to hit, and 
where to fret it.  I've mentioned how to get an idea of note lengths
by looking at the spaces between notes on the TAB, but this can only
be a rough guide. You will always have to check with the original track
to work out details of the rhythm.

A lot of other imprtant information can be included in a piece of TAB.
This includes hammer-ons, pull offs, slides, bends, vibrato and so on.

The standard practice is to write extra letters or symbols between notes
to indicate how to play them.  Here are the letters/symbols most
often used :

      h - hammer on 
      p - pull off 
      b - bend string up
      r - release bend
      / - slide up
      \ - slide down
      v - vibrato (sometimes written as ~)
      t - right hand tap
      x - play 'note' with heavy damping


That last one, the x, is used to get a choppy, percussive sound.
You usually use your fretting hand to lightly damp the strings so 
that when you pick the note it sounds dead.

Note that the use of 'x' is *totally* different from the use of
an 'x' when giving chord shapes.

For example if you wrote the chord of D, you would see :

   EADGBE
   xx0232


where the 'x's mean do not play this string.

In tab it is implicitly assumed that a string is not played if it is not
marked.  So the same chord in TAB would be :



E-----2-----------------------------------------------------------
B-----3-----------------------------------------------------------
G-----2-----------------------------------------------------------
D-----0-----------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

with no 'x'.  The x is is only used in TAB to represent a heavily
muted string which is picked/strummed to give a percussive sound.

There are a number of other symbols for things like whammy bar bends,
pick scrapes and so on.  There seems to be no particular standard
way of writing these - details should be given in the TAB to explain
what the symbols mean.

Bass TAB will probably need a few extra symbols to cope with the
different techniques used in bass playing - for example slapping
and 'popping' the string with thumb or middle finger.
You could use 's' for slap and 'p' for pop as long as you wrote 
them *underneath* the lines of tab to distinguish them from slide
and pull off which would be written *on* the lines of tab.

With hammer-ons and pull-offs you might find things like these :


E----------------------------------------------------------------
B----------------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A---------5h7-----------5h7--------------------------------------
E---0--0----------0--0-------------------------------------------


which would mean play the open E twice, then hit the A string at the 
5th fret and hammer on to the 7th fret.


Pull offs look very similar :

E----3p0------------------------------------------------------------
B---------3p0-------------------------------------------------------
G--------------2p0--------------------------------------------------
D-------------------2---------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------


Here we have a descending blues scale using pull-offs to the open
strings. For each pull off you only pick the first note of the pair
with the right hand - so in this example you would pick all the
notes on the 3rd and 2nd frets, and the open strings would be
sounded by pulling off.


Because you give the string an extra bit of energy when you hammer on
and pull off, you only need to hit the first note with the picking hand.
You could even have a long string of hammer-ons and pull-offs like
this :


E----------------------------------------------------------------
B----------------------------------------------------------------
G---2h4p2h4p2h4p2h4p2h4p2----------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

In this case you only pick the first note.

When bends are involved you need to know how much to bend the note
up. This is indicated by writing a number after the 'b'.
For example, if you see this :

E----------------------------------------------------------------
B------7b9-------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------


it means strike the B string at the 7th fret, then bend the note up 
two semitones (one whole step) so that it sounds the same pitch as
a note fretted at the 9th fret would do. (Sometimes the bend is
written with the second part in brackets, like this ---7b(9)--- )

Something like this :

E----------------------------------------------------------------
B------7b9--9r7--------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------


means play the note at the 7th fret, bend up two semitones, strike the 
note again whilst it is still bent, then release the bend so that the 
note has it's normal pitch. 

You sometimes get a note which is bent up only a quarter of a tone or so.
In this case it would look a bit strange to write :

B--------7b7.5--------

if you have to bend it up half a fret's worth.
Instead it's written as :


      bend up 1/4 tone
E----------------------------------------------------------------
B------7b--------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

with instructions on how much to bend written above the note.

The most common symbols used for slides are / for a slide
up and \ for a slide down.

You might also see 's' used to mean slide.

You don't always need separate symbols for 'up' and 'down' slides
since a line of TAB reading :

E----------------------------------------------------------------
B------7/9-------------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

is clearly a slide *up* from 7th to 9th fret. However you might 
also see things like these :

E----------------------------------------------------------------
B------/7-9-7\---------------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

where the exact start or finish of a slide is not given. Here you
have to know whether you're sliding up or down. In these cases use 
your judgement to choose the starting or finishing fret. The effect 
usually desired is to have a note 'swooping in' from a lower pitch 
or dropping suddenly in pitch as the note fades.


You could have a whole series of slides running together, like this

E----------------------------------------------------------------
B------7/9/11\9\7\6\7--------------------------------------------
G----------------------------------------------------------------
D----------------------------------------------------------------
A----------------------------------------------------------------
E----------------------------------------------------------------

which would mean you only strike the first note with the pick using
the sustain to produce the other notes.

Occasionally you will find TAB which includes information on all
of the note lengths. There seems to be no particular 'standard'
way of doing this, but it usually involves a line of letters or
symbols above the TAB.

If the explanation of the timing symbols is not given in the TAB
then you've got a problem !
In this case a quick email to the author to ask for enlightenment
is the only way forward.