Some people say that it is "playing as fast as you can" but that is not true. Tremolo picking can be difficult especially when you adding other techniques such as string skips, sweeps, and hammer on/pull offs.
Tremolo picking can be seen in tabs as this.
E|-0-0-0-0-0-0-0-0-2-2-2-2-2-2-2-2-3-3-3-3-3-3-3-3----------------------
B|----------------------------------------------------------------------
G|----------------------------------------------------------------------
D|----------------------------------------------------------------------
A|----------------------------------------------------------------------
E|----------------------------------------------------------------------
The picking must be tight and in rhythm. Usually, you will see tremolo picking in sets of 4 or 8 note sets. This IS NOT the only way. In fact, I made a riff using tremolo picking using triplets, and it still works.
The first thing to do is play the example above in 4th notes. When your ready, go into 8ths, then into 16ths. The idea is to try and stay in time. You must use a pick if you want to go fast when you first start. Practice holding your pick correctly because if you hold it incorrectly, it may be difficult doing things like string skips while tremolo picking.
Now, the first time I heard of tremolo picking it was from Emperor's album, Into The Nightside Eclipse on there first track Into the Infinity of Thoughts. The beginning of that song uses tremolo picking, with large string skips, and is pretty difficult to pull off.
E|-----------------0-0-0-0----------|-------------------0-0-0-0----------|
B|----------------------------------|------------------------------------|
G|----------------------------------|------------------------------------|
D|---------2-2-2-2----------2-2-2-2-|----------2-2-2-2-----------2-2-2-2-|
A|-0-0-0-0--------------------------|-0-0-0-0----------------------------|
E|----------------------------------|------------------------------------|
|----------------------------------|----------------------------------|
|------------------0-0-0-0---------|------------------0-0-0-0---------|
|----------------------------------|----------------------------------|
|----------------------------------|----------------------------------|
|--0-0-0-0-2-2-2-2---------2-2-2-2-|--0-0-0-0-2-2-2-2---------2-2-2-2-|
|----------------------------------|----------------------------------|
This is just an example so I won't show the entire thing, but feel free to listen to the song if you have not yet heard it yet. String skipping might seem easy, but when you jumping 3 whole strings, it can be extremely confusing and frustrating to do it and keep in time. Practice makes perfect, so start slowly like before, and slowly work up. Most of the time, string skips will not involve 3 strings, so start string skips using both 1 and 2 string skip such as this example.
1-string skip example 2-string skip example
E|---------------------------------|--------------------------|
B|---------------------------------|--------------------------|
G|-----------------5-5-5-5-3-3-3-3-|--------------------------|
D|-0-0-0-0-3-3-3-3-----------------|-----------------4-4-4-4--|
A|---------------------------------|--------------------------|
E|---------------------------------|-0-0-0-0-3-3-3-3----------|
Now, usually tremolo picking refers to one single note. But in cases it can be used in chords as well. In Mayhem's famous song Freezing Moon, the guitarist Euronymous uses power chords in a tremolo picking fashion with unusual chord progressions.
E|--------------------------------------------------------------------|
B|--------------------------------------------------------------------|
G|-----------------------------------9-9-9-9-9-9-9-9------------------|
D|-2-2-2-2-2-2-2-2--8-8-8-8-8-8-8-8--9-9-9-9-9-9-9-9--8-8-8-8-8-8-8-8-|
A|-2-2-2-2-2-2-2-2--8-8-8-8-8-8-8-8--7-7-7-7-7-7-7-7--8-8-8-8-8-8-8-8-|
E|-0-0-0-0-0-0-0-0--6-6-6-6-6-6-6-6-------------------6-6-6-6-6-6-6-6-|
This can also be seen in the song Under A Funeral Moon by Darkthrone.
e|-----------------------------------------------------------------|
B|-----------------------------------------------------------------|
G|-----------------------------------------------------------------|
D|-----------------8-8-8-8-8-8-8-8--9-9-9-9-9-9-9-9--8-8-8-8-8-8---|
A|2-2-2-2-2-2-2-2--6-6-6-6-6-6-6-6--7-7-7-7-7-7-7-7--6-6-6-6-6-6---|
E|0-0-0-0-0-0-0-0--------------------------------------------------|
Remember! These two songs are played using 16th notes! Tremolo picking is not nearly as good if you cannot stay on rhythm. Sure, playing fast is cool, but if you can play fast and stay on rhythm, then your getting somewhere. Tremolo picking is extremely useful when writing black metal and other metal, and maybe used in other genres, however I have only seen it in black metal.
Good luck to all of you and have fun!
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