Learning AJAX? any good source?

I went through many lesson on AJAX tutorial in the web. But in all i seen only some expamle and a plenty of explaination instead of a good lesson.

Can any one suggest me an easy source of learning AJAX?

Check this tutorial from Mozilla.
http://developer.mozilla.org/en/docs/AJAX

Cheers,
Ess

Here is another worth a look:

http://www-128.ibm.com/developerworks/views/web/libraryview.jsp?search_by=Mastering+Ajax

Andy