Here are the things you need to know and learn.
Also have a look - http://en.wikipedia.org/wiki/List_of_JavaScript_libraries
Framework
- JQuery
- JQuery Mobile
- Node.js
- Ember.js
Pattern
- Knockout.js
- Backbone.js
- Underscore.js
- Angular.js
- Socket.IO
Unit Test
- QUnit.js
- Jasmine.js and Jasmin-jquery.js
Debug
- JHint.js
Function
- Require.js - javascript file loader
- Moment.js - nice date formating lib
- Modernizr.js - device feature detection
- Prettifier - http://code.google.com/p/google-code-prettify/
