Excellent book for anyone starting out with XQuery. Often XQuery books start with the history of XML and descriptions of a plethora of supporting technologies before actually getting to the information you're looking for. You find yourself lost in a sea of acronyms and all you want is to be able to write some XQuery. This book just dives in and gets you started writing XQuery immediately. It's concise and illuminating. If you come from a sql background, it will help get you in an XQuery mindset and will help you to understand how to query and organize your code successfully. The author provides code samples available for download and links throughout for more resources to help you increase your understanding. This is the first time I read a book online in pdf format and it worked for me. The author has a down to earth, conversational style, but is also very knowledgable, so its a fun, quick, and very helpful read.