This talk explores all the techniques used to build a robust, reusable,  cross-platform JavaScript Library. We’ll look at how to write a solid JavaScript  API, show you how to use functional programming to create contained, concise,  code, and delve deep into common cross browser issues that you’ll have to solve  in order to have a successful library.
John Resig is a JavaScript Evangelist,  working for the Mozilla Corporation, and the author of the book ‘Pro Javascript  Techniques.’ He’s also the creator and lead developer of the jQuery JavaScript  library and the co-designer of the FUEL JavaScript library (included in Firefox  3).