Prototype is really a horrible framework. It works by adding methods to every class in the language, even when they don't make sense. This makes for a bit of syntactic sugar, but it also ensures that you can't use other frameworks and that custom code might become very hard to debug.

For your own sake, use anything else.

Layering frameworks probably isn't a good idea to begin with. Prototype does seem, unfortunately, more powerful than jQuery, though, when it comes to class creation.

Thanks.

That's exactly what I really wanted to learn -- know what goes on under the surface and how everything interacts, so I could build upon it.

I think I have already went through the w3schools tutorials a while ago. If you come across any others please let me know

why dont you get hold of any of these books

1) Pro JavaScript Techniques by John resig

2) Professional JavaScript For Web Developers - Nicholas Zakas

I would recommend these two books to anyone who wants to learn JavaScript and XHR. Ajax is very small part fo the whole picture if you are totally new to javascript