al or local) 707-829-0104 (fax) We have a web page for this book, where we list errata, examples, and any additional information. You can access this page at: http://www.oreilly.com/catalog/9781449387860 To comment or ask technical questions about this book, send email to: bookquestions@oreilly.com For more information about our books, courses, conferences, and news, see our website at http://www.oreilly.com. Find us on Facebook: http://facebook.com/oreilly Follow us on Twitter: http://twitter.com/oreillymedia Watch us on YouTube: http://www.youtube.com/oreillymedia Preface Safari® Books Online Safari Safari Books Online is an on-demand digital library that lets you easily Books Online search over 7,500 technology and creative reference books and videos to find the answers you need quickly. With a subscription, you can read any page and watch any video from our library online. Read books on your cell phone and mobile devices. Access new titles before they are available for print, and get exclusive access to manuscripts in development and post feedback for the authors. Copy and paste code samples, organize your favorites, down- load chapters, bookmark key sections, create notes, print out pages, and benefit from tons of other time-saving features. O'Reilly Media has uploaded this book to the Safari Books Online service. To have full digital access to this book and others on similar topics from O'Reilly and other pub- lishers, sign up for free at http://my.safaribooksonline.com. Acknowledgments Writing a book is hard work-far harder than I ever imagined. Though I spent countless hours alone in front of a keyboard, I could not have accomplished the task without the help of many others. I would like to thank my lovely wife, Lauren, for being patient, loving, and supportive. Lauren, being my in-house proofreader, was also the first line of defense against gram- matical snafus. Many of the chapters no doubt bored her to tears, but I know she enjoyed at least a few. Thank you for helping me achieve this goal in my life.