What is AJAX? Is it a language? Is it a product? It is neither. AJAX is a web development technique for creating interactive web applications using a combination of technologies such as XHTML, Javascript, and CSS. When these technologies are used in conjunction with each other, the slickness of a desktop application becomes attainable on the Web. Because of this capability, AJAX is taking the web community by storm. Google serves as the poster child for this phenenomenon(a current search of the term on Google itself yields more than 7 million results) and other companies are quickly following suit. This book is an example-based overview of each technology AJAX uses. By using substantial amounts of code, the book introduces each technology and then shows how to combine the elements of each to create Rich Internet Applications (RIAs). Starting with a few simple techniques and adding the more complex techniques as each prior one is mastered, the reader is given an understanding of the concepts behind AJAX while simultaneously creating RIAs. For instance, if the reader is only comfortable with HTML and JavaScript - there are recipes for AJAX that require only those two elements. The reader will have the ability to stop reading at any time and employ the techniques that have been covered to that point. Specific coverage that will appeal to the open source developer community has also been included, such as Ruby on Rails, KDE, GNOME, and Firefox.