With the new available JavaScript library available, JavaScript programming will get even more easy. The new library I am talking about is jLinq - a JavaScript Query Language.
jLinq is a Javascript library that lets you write queries against arrays of javascript objects.
jLinq is completely extensible so you can write your add-ins and they will work with the rest of the framework without any additional programming!
Other JavaScript library and framework includes: jQuery, Mootools, Prototype, Dojo, script.aculo.us, YUI among others.