How do people remember a whole song on guitar?

I just dont get it, take steve vai for insatance, for the love of god is long, he remembers it all, or lynard skynards freebird, how can those guitaist remember all of it? its insance. I can't remember a song worth CRAP! haha possibly something that...

comes with time.

If you practise a song enough times, you will gain muscle memory and your fingers will just go to the right notes automatically without you really concentrating on it.

Music, like anything, just takes a lot of time and practice. You have to be passionate about it.

yea and be sure that you are really devoted to what you are doing. cause if not you cant really master it that instant!

Exactly what odal said. I can remember long songs to and play them back by memorie.

thanks guys.. wish me luck on canon rock lol