Hey people!, you know I was looking what it mean riff and you know what? I can't found it!!!

So, please somebody can explaint to me what is a riff? How do you do a riff?

sorry, but i have to say this...

asking "what is a riff?" as a guitarist is like a man asking "what is a penis?"

I just had to get that off first, now to the question

A riff is basically a line or a melodic composition that makes up a part of a song (usually the main part of the song) by the given instrument (usually Guitar in rock music). Its like the intro to say Smoke on the Water. Thats an example of a guitar riff.
A riff is the same as a lick :P And if you dont know what a lick is, play around by fingering the G string until it makes noise. If you like the noise keep doing it, and that, my friend, is a riff, which is a lick.
I've always thought of riffs to be a theme for a song, usually catchy.. such as Crazy Train, Black Dog, Paranoid etc, which can include chords and single notes, and for some reason I believe that they'd be played on the lower end.

I think of licks as phrases, or flurries, of notes, usally played on mid/higher end, and would be used more of an interlude. A solo would be a number of licks smoothly connected together.

Although this is how I've perceived the two 'words', and of course are not solid rules to either.