First of all, a guitar tab is form of notation that documents 
the notes of a song. It shows which strings to hit, and where to
fret the strings.  However, there is NO exact indication for the 
timing of each note.  The notes are usually spaced out to loosely
represent each notes timing, but a knowledge of the songs rhythm
beforehand is pretty much required.

This is the way the guitar strings are represented in tablature notation: 
              
e|-----------------------------------|
B|-----------------------------------|
G|-----------------------------------|
D|-----------------------------------|
A|-----------------------------------|
E|-----------------------------------|
  
The top string is the high "e" string which, if you have the guitar
in playing position, is the furthest away from your body.  So if
you were to lay the guitar down on your lap and look at it from a
bird eye's view, the strings will line up with the tab perfectly.  The string
closest to you is the low "E" and the string furthest away is the high "e".
The high 'e' is called string 1, the B is string 2, and so on.

The numbers on the tab represent which fret is to be used on each string.
So in the following example, you would fret the 2nd fret on the A string:

e|-----|
B|-----|
G|-----|
D|-----|
A|--2--|
E|-----|

Numbers are spaced left to right, so three notes played in a row would 
look like:

e|-----------|
B|-----------|
G|-----------|
D|-----------|
A|--2--3--4--|
E|-----------|

So in the above example, you'd fret the A string on the 2nd fret, hit that
note, then fret the 3rd fret, hit that note, then fret the 4th fret, hit
that note.

If a zero is shown on the tab, that means you don't fret anything and
just strike the string, called an open note. 

e|--------|
B|--------|
G|--------|
D|--------|
A|--0--0--|
E|--------| 

So the above would have you just strike the A string twice without
fretting anything.  


If numbers are lined up in the same vertical line, that means you play 
them together.  So in the following example, you'd fret both
the A string AND the D string on the 2nd fret, and hit both strings at the
same time:

e|-----|
B|-----|
G|-----|
D|--2--|
A|--2--|
E|-----|

Strumming chords will either look like that, or they can be shown in a different
way.  Here are two ways to show an E minor chord strummed:

e|--0--|
B|--0--|
G|--0--|
D|--2--|
A|--2--|
E|--0--|

e|------0-|
B|-----0--|
G|----0---|
D|---2----|
A|--2-----|
E|-0------|

The first one would be strumming all the strings at once, at least, as
close as possible.  The second one would most likely represent a slower
strum, but the notes would still be very close together.  As you can see,
this is a perfect example of where knowing the songs rhythm is necessary.

One more example of how tabs can somewhat show timing.  In the following 
example, the notes will gradually get faster:

e|--------------------------------------------|
B|--------------------------------------------|
G|--------------------------------------------|
D|--------------------------------------------|
A|--------------------------------------------|
E|-0----0----0--0--0--0--000-0-000-0-00000000-|

You'll notice that towards the end, the space between notes is zero.
This can become confusing sometimes though, as in the following example:

e|-----------------------------------|
B|-----------------------------------|
G|-----------------------------------|
D|-1111-11-1111-11-1111-11-----------|
A|-----------------------------------|
E|-----------------------------------|

We don't know if that means to hit the '1' fret four times, then pause,
then hit the '1' fret two more times, then pause, etc, OR if it means to
hit the '11' fret twice really fast, then pause, hit the '11' fret once,
then pause, etc.  It could even be a combination of those two.

Usually you'll be able to tell which way is right by what other notes
are around it, or by knowing the songs rhythm.  However for the tabs on 
this site, to eliminate ambiguity, if a double-digit fret is hit more than once
very rapidly, there will always be at least one space inbetween them.  So in the
above example, you would know it must be the '1' fret being used.

Similarly, single-digit frets will always have a space inbetween them unless it
is the same note being played.  So in the following example:

e|---------------|
B|---------------|
G|---------------|
D|--23-23-23-23--|
A|---------------|
E|---------------|

That means the 23rd fret is being hit 4 times, not the 2nd and 3rd fret
back to back 4 times. 

Now on to the specific details.  The following notations change depending
on who is writing the tabs, but once you know one system, you should be
comfortable with them all.  The following is the system this site has
adopted and a notation key can be found at the end of each tab for reference.


Notation:

1. Palm muting

Palm muting is when you rest your picking hand on the strings just enough
to prevent it from ringing.  Different amounts of pressure will produce
different sounding mutes, but that's the basic idea.  You rest the side/edge
of your palm on the strings to prevent ringing.  In metal, you also use this
to create the crunch sound.  Palm mutes are noted as follows:

e|-----------------|
B|-----------------|
G|-----------------|
D|-----------------|
A|-----3-3-----5-5-|
E|-2-2-----2-2-----|
   * * * * * *

2. Fret-hand muting

This is done by lightly resting your fret hand across the strings so you're
touching them, but not pushing down on them, then striking the strings like
normal.  Instead of notes, you'll get a "rake" sound, and when combined with
a mute from your picking hand (as described above), you'll get a thick sounding
rake (i.e. the intro to Megadeth's Train of Consequences).

Be careful where you rest your fret hand when doing these though, as some
places will produce a harmonic instead (harmonics are discussed later). 
Here's the notation:

e|-------------|
B|-------------|
G|-------------|
D|-------------|
A|-x-x-2-2-x-x-|
E|-x-x-0-0-x-x-|

Usually you just "feel" for how many strings to strike when you mute with
your fret hand.  The tabs on this site will only show two 'x's to represent
all mutes that involve two or more strings.  But really, just use whichever
sounds best to you, you usually just strum the strings and don't care how
many you're hitting.  However, if only one 'x' is present, then only mute
and strike that string, as in the following example:

e|-----------------|
B|-----------------|
G|-5-6-7-x---------|
D|---------5-6-7---|
A|---------------x-|
E|-----------------|


3. Bending

Bending a note is represented as follows:

e|---------------|
B|---------------|
G|---2b4---------|
D|---------------|
A|---------------|
E|---------------|

That would mean you hit the note on the 2nd fret, then bend the
string until the note reaches the same pitch as the note found at
the 4th fret.  There are different types of bends, probably the most
popular are:

A half-step bend is when you bend the note up a fret, such as:

e|---------------|
B|---------------|
G|------4b5------|
D|-2b3-----------|
A|-----------6b7-|
E|---------------|

A full-step bend is when you bend the note up two frets, such as:

e|---------------|
B|---------------|
G|------4b6------|
D|-2b4-----------|
A|-----------6b8-|
E|---------------|

A quarter-step bend is a small bend that only goes up half a fret.
Instead of using the same pattern and noting quarter-step bends like this:

e|---------------|
B|---------------|
G|---------------|
D|--2b2.5--------|
A|---------------|
E|---------------|

We've decided to just use this notation:

e|---------------|
B|---------------|
G|---------------|
D|--2^-----------|
A|---------------|
E|---------------|

If you are to bend a note, then release the bend back down to the
original note, it will be noted as follows:

e|---------------|
B|---------------|
G|---------------|
D|---2b4r2-------|
A|---------------|
E|---------------|

So after bending it and reaching the 4th fret note, you slowly let the
string go back to the original note.  A note isn't always released to
its original position however, so you may see this:

e|---------------|
B|-19b22r20------|
G|---------------|
D|---------------|
A|---------------|
E|---------------|

Sometimes a bend is supposed to be held for a long time before it is 
released.  Tablature doesn't accurately represent timing remember, but to
help you out, we try to help out by using this notation:

e|-----------------|
B|-----------------|
G|-19b21---(21)r19-|
D|-----------------|
A|-----------------|
E|-----------------|

The note in parenthesis ALWAYS represents the actual NOTE being played,
NOT the fret.  So the above means that you do the bend from the 19th fret,
then later you'll still have that 21-fret note ringing, so now it's time
to release it.  The note in parenthesis is called a ghost note because you
don't actually hit it, it was produced by a previous action.

While on the subject of ghost notes, you may see them in other places but 
always remember that they just represent a note that you'll hear, they don't
represent a fret to play.  So in the following:

e|---------------|
B|---------------|
G|---------5-----|
D|---7----(7)----|
A|---------------|
E|---------------|

That just tells you that the sound of the 7th fret note should still be
ringing when you hit the next note, the 5th fret note.  You NEVER pick a
ghost note.

Back to bending, sometimes a note requires you to bend the string first, THEN
hit the string.
These are called pre-bends, and are noted as follows:

e|---------------|
B|-[17]19r17-----|
G|---------------|
D|---------------|
A|---------------|
E|---------------|

This means you start at the 17th fret, bend it the proper amount so that it
will ring out the same note as the 19th fret, THEN strike the string, then
release the string back to the 17th fret note.

If you ever see a note surrounded by curled brackets, like:

e|---------------|
B|---------{15}--|
G|--12b14--------|
D|---------------|
A|---------------|
E|---------------|

That means you are supposed to hit that note while holding the previous
bend.  We could have used a ghost note and notated this as:

e|---------------|
B|----------15---|
G|--12b14--(14)--|
D|---------------|
A|---------------|
E|---------------|

But sometimes the note to be struck during the bend is on the same
string as the bend, so it wouldn't be possible to use that notation.
So the curley brackets will be used instead.

Unison bends you should be able to figure out after knowing all the above,
but just to clarify:

e|---------------|
B|--10-----------|
G|--12b14--------|
D|---------------|
A|---------------|
E|---------------|

The above example means you hit the 10th fret and 12th fret at the same time,
but then while holding the note on the B string, you bend the G string.

The last thing to discuss about bends are bends done by use of the 
tremolo bar, or more popular labeled, the whammy bar.  These bends
will be noted with a '*' symbol following the bend, so:

e|-----------------|
B|-----------------|
G|--12b15*---------|
D|----------14d10*-|
A|-----------------|
E|-----------------|

The above represents a whammy bar bend and a whammy bar release, usually
called a dive which is why a 'd' is used instead of the normal 'r'.  


4. Hammer-ons and Pull-offs

A hammer-on is when you strike a note, then push another finger down
on another fret to produce another note.  So essentially, you get two notes
for one pick.  So in the following example:

e|-----------------|
B|-----------------|
G|-----------------|
D|-5h7--7h9--5h6h7-|
A|-----------------|
E|-----------------|

You only pick the D string 3 times in that example, the other notes are
made by pushing another finger down on that fret hard enough to make it ring.
You can use whichever finger(s) is(are) most comfortable.

Pull-offs are the opposite of hammer-ons.  You strike a note, then rip your
finger off of that fret to produce a note that another finger is already
fretting.  So for example:

e|-----------------|
B|-----------------|
G|-----------------|
D|---9p7-----------|
A|-----------------|
E|-----------------|

You would have your fingers fretting the 7 and the 9 on the D string.
You strike the D string, producing the note of the 9th fret.  Then you "rip"
your finger off, leaving the finger that is fretting the 7 on there.  This
will you give the 7th fret note "for free".  When you rip your finger off,
try pulling it off the string at an angle until you get the hang of it.  And
just like hammer-ons, there can be multiple notes in a pull-off too, like:

e|--------------------|
B|--------------------|
G|-12p11p10p9--10p9p0-|
D|--------------------|
A|--------------------|
E|--------------------|

Two strikes of the G string is all that's required for the above example.
All you do is keep ripping your fingers off until reach the last note.  To 
bring up the ghost note again, if you see this:

e|-----------------|
B|-----------------|
G|-10p9----(9)p7---|
D|-----------------|
A|-----------------|
E|-----------------|

That is still only one pick.  You pick the 10th fret, pull off to the 9th
fret, then you hold that note for awhile, then pull off again to the 7th fret.


5. Slides

Slides are similar to hammer-ons and pull-offs in that they let you combine
notes in a very fluid manner.  To slide, all you do is hit a note, then while
it's still ringing you slide your finger that was fretting that note to the
next fret shown on the tab.  So in the following example:

e|-----------------|
B|-----------------|
G|-----------------|
D|-----------------|
A|-2/5--5/7--7\3---|
E|-----------------|
 

You strike the 2nd fret, then slide up to the 5th fret...two notes for one
pick.  Do the same for the next slide, then the final slide is a slide down.
Same procedure, you just go down the fretboard instead.  If there is a space
between slides, as in the above example, that means you pick the beginning of
each one.  If there are two or more slide notations in a row, that means you
stop at each fret number, but don't strike the string again, just go to the
next fret.  So in the following:

e|-----------------------------|
B|-----------------------------|
G|-----------------------------|
D|-----4/5-5/7/8\-5\4-5\4-5/7--|
A|-3/5-------------------------|
E|-----------------------------|

There are six pick strikes in the above example.  The third slide is just
striking the 5th fret, sliding to the 7th fret, pausing for a brief second, 
then continuing on to the 8th fret, pausing for a brief second, then sliding 
down to the 5th fret for the next slide.  

If you ever see a slide notation and no number preceding or trailing it,
like this:

e|------------------|
B|------------------|
G|------------------|
D|-----5-6-7--------|
A|-5\------------/7-|
E|-------------0----|

The first one doesn't tell you where to stop the slide.  This means it's
pretty much up to you when to stop it, it is a "feel" technique.  You usually
only slide for a few frets though, then stop and continue on, but it depends
on the song.  For the second slide, it doesn't tell you where to begin the
slide.  So again, just feel for where to start the slide, although
it typically happens a few frets before the note shown.


6. Vibrato

Vibrato is just vibrating the string rapidly after hitting a note.
The speed of the vibrato can only be determined by listening to the song,
although the length of the vibrato notation can be used to estimate how
long each one lasts, like this:

e|-----------------|
B|-----------------|
G|-----------------|
D|-5~--5~--5~~~~---|
A|-----------------|
E|-----------------|

The third note's vibrato lasts longer than the first two.

If the whammy bar is used to vibrate a note, a '*' symbol will be attached
to the vibrato symbol, like this:

e|-----------------|
B|-----------------|
G|-----------------|
D|--5~*------------|
A|-----------------|
E|-----------------|


7. Tremolo picking

Tremolo picking is when you pick a note very rapidly.  Because it is
hard to count the number of times a note is struck during tremolo picking,
it is respresented as follows:

e|-----------------|
B|-----------------|
G|-----------------|
D|--3tm--5tm-------|
A|-----------------|
E|-----------------|

So you just pick the 3rd fret very rapidly, then when the song requires you to,
you change to the 5th fret and pick that very rapidly.  


8. Trill

Trills are a series of very rapid hammer-ons and pull-offs.  Similar to the
tremolo picking, instead of counting how many times the notes are played,
we just use a simple notation.  So instead of this:

e|-----------------------------|
B|-----------------------------|
G|-----------------------------|
D|-5h7p5h7p5h7p5h7p5h7p5...etc-|
A|-----------------------------|
E|-----------------------------|

The following shorthand will be used:

e|-----------------|
B|-----------------|
G|-----------------|
D|--5tr7-----------|
A|-----------------|
E|-----------------|


9. Pick slide:

Pick slide is when you take the edge of your pick and run it along a 
string (usually the low 'E' string) to produce a scratchy rough noise.
You have to experiment with speed, location, and duration of the slides
in order to get the desired sound.  Pick slides are shown as follows:

e|-------------|
B|-------------|
G|-------------|
D|-------------|
A|-------------|
E|-5-6-7--X\\--|


10.  Harmonics

There are 3 types of harmonics:  Natural, artificial (or pinch), and touch.

Natural harmonics are made by lightly placing your finger over a certain part
of the string and stricking it.  You don't fret the string, you don't even 
really touch it, you just lightly graze it with your finger.  Some spots will
produce dead sounds, but certain places will produce crisp high notes.  Some
of these places are right above the 5th and 12th frets.  If a note is to be
played as a natural harmonic, it will look like this:

e|------------------|
B|----12------------|
G|----h.------------|
D|-5-----5----------|
A|-h.----h.---------|
E|----------12------|
            h.

So you lightly place your finger directly above the 5th fret bar on the
D string on the fret board, then strike the string.  After the note is made,
you can take your finger away and the note should still sound.  Repeat this
procedure for the next 3 notes.  

Artificial, or pinch, harmonics can be done anywhere on any strings.
These harmonics are harder than the natural ones and usually require a lot
of practice.  It's hard to describe how to do them, and there are even 
different ways to do them, but maybe the most popular way is like this:

After you fret a note, choke up on the pick so that just a little bit is 
showing.  Then when you strike the string, try and make the edge of your thumb
just graze the string RIGHT after the pick strikes it, so it's almost as one
motion.  The result will be a higher pitched sound than normal.  When combined
with vibrato, you'll get those squeals that are characteristic of metal
guitarists
such as Dimebag Darrell from Pantera or Zakk Wylde from Ozzy Osbourne and Black
Label Society.

Once you can hear it and know what these pinch harmonics are, experiment until
you
find a way to do them that is easy and comfortable for YOU.  For beginners,
try using the G string around the 7th or 9th fret to make a pinch harmonic.
You'll know if it worked because the note will be very high pitched.  Once
you get the hang of it, try it on the low E.  

Here is how artificial harmonics will be labeled:

e|------------------|
B|------------------|
G|------------------|
D|------------------|
A|------5~-------2--|
E|--3~--a---3-2--0--|
    a       a a

The last type of harmonic is the touch harmonic.  These are similar to
natural harmonics except you have a note already ringing before you do them.
You strike a note on some string, then while the note is still ringing, you
lightly touch that string somewhere else to produce a higher pitched note.
These are represented as follows:

e|-----------------|
B|-----------------|
G|-----------------|
D|-7------<12>-----|
A|-----------------|
E|-----------------|


11. Finger tapping

Finger tapping is essentially using your finger to pick a note rather
than your pick.  It's usually combined with pull-offs or hammer-ons to
create a very fluid sounding chain of notes.  To finger tap, you usually
fret a certain note, then using a finger from your picking hand, you slam
it down on a fret higher up than the one that was already fretted.  So in 
the following example:

e|--12t8--|
B|--------|
G|--------|
D|--------|
A|--------|
E|--------|

You would fret the 8th fret like normal, then use a finger from your picking
hand and slam it down on the 12th fret, then rip it off.  The result is a form
of pull-off, except your finger picked the string, not the pick.

Usually you will see finger tapping in one of these forms:

e|-12t8p5-13t5h8---|
B|-----------------|
G|-----------------|
D|-----------------|
A|-----------------|
E|-----------------|

The first tap is the same as the previous example except after ripping your
finger off the 12th fret, you rip your other finger off of the 8th fret.  The second
tap is just using a hammer-on instead of a pull-off after tapping the string.

You can tap the string with your index or middle finger, but using your middle
finger allows you to keep the pick in your hand as you would normally hold it.  So it
may be easier to go right back to using the pick after tapping if you use your
middle finger.