I draw comics. Nothing professional, just for fun right now, but I know that at least in Pshop that a .jpg is what you want to save your files in so that you can upload to the web.
But what about Illustrator? When you open Illustrator, you are given a few Document Profiles to work with. I may be overlooking the obvious, in that one of them IS "web document", but who knows if that is really the best choice.
Just checking before I dive in and save all my files in the wrong format.