jQuery UI is a collection of GUI widgets, animated visual effects, and themes implemented with jQuery, Cascading Style Sheets, and HTML.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Prototype is a JavaScript Framework that aims to ease development of web applications.
RackCache is a quick drop-in component to enable HTTP caching for Rack-based applications.