XML, the Extensible Markup Language, is everywhere: the syntax of choice for newly designed document formats across almost all computer applications. Now used daily by developers, XML is living up to its reputation as one of the most important developments in document interchange in the history of computing. A perennial bestseller, the handy "XML Pocket Reference" from O'Reilly has been revised once again to give you quick access to the latest goods. In addition to its comprehensive look at XML, this third edition has been updated with new material on Namespaces and XML Schema--considered among the most important elements in current XML use--along with RELAX NG and Schematron, additional powerful tools for describing XML document structures. Like other titles in O'Reilly's Pocket Reference series, the "XML Pocket Reference," 3rd Edition features a well-organized format that gets right to the point. As a result, it's already won over the allegiance of developers everywhere. If you need XML answers quick and on the fly, this compact book is most definitely the book for you.