I've listened to some bands but still don't really get what exactly the lead guitar does, Here is my personal review
-Intro- lead guitar plays a certain riff reapeted
-Verse/chorus- same as above
-fills between verse and chorus- guitar plays a certain melody line
-Solo- same as above
Now I'm wondering if that's pretty much it, think of a riff and repeat it over and over again and then if you change parts in the song change the riff. If so how can you memorize all these riffs and how can you write them. Also I can see that guitarists usually memorize their solos. How can you memorize it. Do you just record it once and listen to it over and over again, or do you tab it down for later use?

Same as any instrument. You play the song over and over again until it's memorized! And yes, it can sometimes become boring, but it's worth it in the end!

Edit: I guess you could repeat the same thing over and over, but it would get REALLY boring for you and the audience. You should just experiment with the parts until you feel really excited about what you've created.

I think you're getting too technical. Most musicians have a wicked awesome solo or whatever that you hear on the album, but when they play it live, it's changed up a bit each time. To write it yourself, you mostly just play. I don't think it's so much planning out what to play as much as it is just playing. If you like it, play it again. If not, play something else.

Then if you want to write it down, use tabs with typical formatting so everyone else can read them.

If you want to practice, I use JamStudio.com. You can make a song with your own chord progression and instrumentation, loop it, and play along with. Check it out.

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- the highjumper
http://www.jamstudio.com

Hey HighJumper, I agree with you. I have been using Jamstudio.com for a month or so now and my music has grown so much. It is such a sweet thing to be able to use!

You need to know the key the song/riff is in. The easiest way to write down a solo is to choose a scale that applies to this key and then from there paint it down. Whether it's legato, pull offs or straight alt. picking runs. If you have an A minor dominated chord progression then you have to figure, a minor scale, minor diminished or minor pentatonic might fit well, all though it is interesting to try a major scale or chromatic on top, that is if you choose the right selection of notes in the scale and how they blend with the rhythm.

Though I understood that, I am pretty sure that if he is asking this question in the first place that he has no idea what any of that meant.