Source: http://speckyboy.com/2008/04/01/top-10-javascript-frameworks-which-do-you-prefer/

1. script.aculo.us (http://script.aculo.us/)

URL: http://script.aculo.us/.
Blog: n/a.
Documentation: http://wiki.script.aculo.us/.
Note: script.aculo.us is not a Framework by its self but it is an addon for Prototype.

“script.aculo.us provides you with easy-to-use, cross-browser user interface JavaScript libraries to make your web sites and web applications fly.”

2. Prototype (http://www.prototypejs.org/)

URL: http://www.prototypejs.org/.
Blog: http://www.prototypejs.org/blog.
Documentation: http://www.prototypejs.org/learn.

“Prototype is a JavaScript Framework that aims to ease development of dynamic web applications. Featuring a unique, easy-to-use toolkit for class-driven development and the nicest Ajax library around, Prototype is quickly becoming the codebase of choice for web application developers everywhere.”

3. Moo Tools (http://www.mootools.net/)

URL: http://www.mootools.net/.
Blog: http://blog.mootools.net/.
Documentation: http://docs.mootools.net/.
Demos:http://demos.mootools.net/.

“MooTools is a compact, modular, Object-Oriented JavaScript framework designed for the intermediate to advanced JavaScript developer. It allows you to write powerful, flexible, and cross-browser code with its elegant, well documented, and coherent API.”

4. jQuery (http://jquery.com/)

URL: http://jquery.com/.
Blog: http://jquery.com/blog/.
Documentation: http://docs.jquery.com/.

“jQuery is a fast, concise, JavaScript Library that simplifies how you traverse HTML documents, handle events, perform animations, and add Ajax interactions to your web pages. jQuery is designed to change the way that you write JavaScript”.

5. MochiKit (http://www.mochikit.com/)

URL: http://www.mochikit.com/.
Blog: http://www.mochikit.com/blog.html.
Documentation: http://www.mochikit.com/doc/html/MochiKit/index.html.
Demos:http://www.mochikit.com/demos.html.

“MochiKit - makes JavaScript suck a bit less”.

6. Rialto (http://rialto.improve-technologies.com/wiki/)

URL: http://rialto.improve-technologies.com/wiki/.
Blog: n/a
Documentation: http://rialto.improve-technologies.com/js/doc/.
Demos:http://rialto.improve-technologies.com/rialto/.

“Rialto (Rich Internet Application Toolkit) is ajax-based cross browser javascript widgets library”.

7. Dojo Toolkit (http://dojotoolkit.org)

URL: http://dojotoolkit.org/about.
Blog: http://dojotoolkit.org/blog.
Documentation: http://dojotoolkit.org/docs.
Demos:http://dojotoolkit.org/demos.

“Dojo is an Open Source DHTML toolkit written in JavaScript. Dojo aims to solve some long-standing historical problems with DHTML which prevented mass adoption of dynamic web application development”.

8. Spry Framework (http://labs.adobe.com/technologies/spry/)

URL: http://labs.adobe.com/technologies/spry/.
Blog: n/a.
Documentation: http://www.adobe.com/go/labs_gnav_wiki.
Demos:http://www.adobe.com/go/labs_gnav_showcase.

“The Spry framework for Ajax is a JavaScript library that provides easy-to-use yet powerful Ajax functionality that allows designers to build pages that provide a richer experience for their users. It is designed to take the complexity out of Ajax and allow designers to easily create Web 2.0 pages”.

9. ASP.NET Ajax Framework (http://asp.net/ajax/)

URL: http://asp.net/ajax/.
Blog: n/a.
Documentation: http://asp.net/ajax/documentation/.
Demos:http://asp.net/ajax/showcase/.

“ASP.NET AJAX is a free framework for quickly creating efficient and interactive Web applications that work across all popular browsers”.

10. Cean Ajax Framework (http://sourceforge.net/projects/clean-ajax/)

URL: http://sourceforge.net/projects/clean-ajax/.
Blog: n/a.
Documentation: http://sourceforge.net/docman/?group_id=145307.

“Easy to use AJAX framework that provides message queue, XSLT, XPath, encryption (SHA1, MD5), web service access (SOAP, XMLRPC), JSON-RPC, cross browser AJAX, AJAX history and cache control”.