I've been reading a bit about AJAX lately. Mostly because its the hot topic that everybody on the web is talking about, but also partly because it's pretty darn useful ;-)
I've decided to use it in an application I am developing at work.
This application is suppossed to replace an existing windows app which is partly developed using MFC and partly web-based using IE browser component embedded in the windows application and IE only html. Makes me shiver.
So I decided to develop it using Ruby on Rails and it's builtin support for AJAX.
So what is AJAX
A common limitation with web applications is the request-response model of http. With this model everytime you want some interaction with the server, you pretty much have to reload the entire page. This makes webapplications seem heavy and bothersome compared to native desktop applications.
If you want to see AJAX in action take a look at google maps and script.aculo.us.
I can recommend the links below for learning more about AJAX:
Rasmus' 30 second AJAX Tutorial
Rasmus Lerdorf of PHP fame explains AJAX with a very simple code example, really nice...
Wikipedia has good coverage as usual
State of AJAX.
Originally from slashdot. Links AJAX with Service-Oriented Architectures (SOA). The article is overrated, but it has a lot of good links.