jQuery is a library of functions for JavaScript that provides easy and sophisticated access to the HTML in a web page. Originally intended to smooth over the differences in the way browsers interact with JavaScript, it has developed into a much more powerful tool that fully lives up to its motto of "write less, do more". As a result jQuery is compact and can seem cryptic until you get used its common idioms. Written for JavaScript developers working with web page layout, Just jQuery: The Core UI enables you to use jQuery easily and efficiently. It also cuts through its seeming complexity, by presenting enough explanation at every stage for you to understand what is happening. After outlining what jQuery is, how to obtain it and why you should use it, early chapters deal with the essential jQuery - its selectors, filters and DOM traversal functions. Next we look at how to modify existing HTML elements and how to create completely new elements. Next we look at more advanced aspects of the UI - storing data and working with forms. jQuery also provides simple animation functions and to understand these we look at function queues and asychronous animation. Adding custom elements, both to the jQuery UI and to jQuery itself, is the next major topic. The book closes with an explanation of how jQuery's unit testing package, QUnit, lets you write tests to make sure that your JavaScript code works and continues to work.