Undestanding AJAX - background reading

Dr. Dobb's selected Yahoo! User Interface Library as the best AJAX Framework to fit their web projects' need. A little week in widgets but top score in download size (22k), maintenance, documentation. (Other were: Dojo, Prototype and Scriptaculous, Direct Web Reporting and finaly Google Web Toolkit.

Why it came, when it came and what technology is used, an article over 3 pages from computerworld.com, AJAX

This one us really good, it talks about how these techniques are used instead of baffling about how great it is and what you can do with it, 6 pages from Computerworld.com, Hands On: Understanding AJAX

A looong 7 page article about an application first made with a hidden frame, then how that old technique is replaced by the A-bbreviation, again Computerworld.com So how do you code an AJAX WWeb page?

If you would like to do it yourself and not use the Microsoft AJAX Extensions in Visual Studio or Express you can go to this 7 page article from Professional Technical Reference, Getting Started with AJAX and the AXMLHttpRequest Object

Additional:
JSON JavaScript Object Notation - If you are in need of as little network load as possible you can send and recieve JSON, the Prototype library can help you. Dev2Dev - An introduction to JSON

ScottGu on JSON Hijacking and How ASP.NET AJAX 1.0 Avoids these Attacks

Milan @aspnetresources.com as written a nice set of one-pager pdf files on various MS Ajax types. Download ASP.NET AJAX PDF Cheat Sheets

Don't use AJAX to call time consuming functions

Having an ajax exhaustive site can make performance go down if it has several heavy calls blocking the threads in the available thread pool - because the ajax calls calls a webservice wrapper and weservices are executed synchronously - compared to asp.net normal postbacks that can be asynchronously.
--> When having lots of load on such calls, perform partial or complete postback instead.

Found at: Dr. Dobb's AJAX ans Asynchronous Pages march 13, 2007