Intended for experienced web developers, this guide explains XMLHttpRequest object's properties and methods, how it communicates with the server, and techniques for adding Ajax to an application. Code examples illustrate how to document JavaScript code with JSDoc, validate HTML content with Firefox extensions, search for nodes using DOM Inspector, test JavaScript with JsUnit, and debug Ajax requests with Greasemonkey. Annotation ©2006 Book News, Inc., Portland, OR (booknews.com)