AJAX or other client side scripting

I've been reading over and over that there is a need for client side scripting to lighten server loads. I tend to agree. Currently, Version 3 is all server side. I think I'm going to have to start learning AJAX or something to that nature to keep up with the times. I'd like to see what it can do. I've used Gmail and am impressed with the ease of use and the speed.

Does anyone recommend any books or sites on the topic?

the best resource for just getting an overview of what AJAX can do, u can checkout this article at wikipedia.

I recently used AJAX in one of our company's project, using JSP+MS SQL..must say, it achived what was not previously thought of. I hope ppl actually start taking AJAX seriously.

Are you aware of any alternative client side scripting methods other than AJAX?

javascript, vbscript?? u meant tht..i dont think theres any other client side scripting out there!

ActiveX (crap) is also client and server side. Interestingly enough, Outlook Web Access started AJAX in the right direction. Anyway, what I'm looking for is a site that explains how to parse XML files using javascript. I use PHP and http://www.php.net is a great help for any PHP coder.

What is AJAX...? Like javascript? Also, the user doesn't have to download any program, like flash player I hope. Any examples?