Ajax types most know list

AJAX Library Name	Brief Description
ASP.NET AJAX Extensions ("Atlas")	AJAX functionality for ASP.Net via server components, with auto generated JavaScript and tightly related to server controls.
AJAXPro	Ajax for ASP.NET development to create a fully client-side based and require a few server-side API calls to get/set data
Direct Web Remoting (DWR)	AJAX solution for Java based web solutions.
Dojo	Provides a strong abstraction between them and the browser's DOM Provides the most impressive end effects from the least code
Google Web Toolkit (GWT)	For Java based solutions that require to invest more time to get a more robust, easier-to-debug solution
Prototype	Client-side development that require minimal abstraction between them and the DOM Client-side development that need a library to speed up common DOM manipulation tasks
xAJAX	For PHP development of all stripes

Note: There are the strengths and weaknesses of popular pure JavaScript libraries and a few options offered by the server-based AJAX libraries. AJAX Library Type Pros Cons Server Based Have ability to map native server objects such as database results to JavaScript equivalents Reduce efforts required to code JavaScript (depending on the library) This kind of AJAX library JS code ties tightly to the server language or controls. Pure JavaScript Have ability to handle multiple server languages  Have a clear line of sepration between client and server code In this kind of library developer has to manage the logic for to manage how to translate server-side return values to XML or JSON.