Prototype
According to a survey, Prototype is the most used AJAX framework.
http://www.oreillynet.com/xml/blog/2006/07/whats_the_best_ajax_toolkitfra.html
A little while ago, I wrote about the GWT (Google Web Toolkit) here, which I'm particularly interested in as it provides a pure Java environment that can be translated into pure AJAX-style code. This means that a Java developer can work with the GWT and create effective, lightweight, interactive websites without the need to …