Ayers Danny - Beginning XML

Beginning XML, 4th Edition

Published by

Wiley Publishing, Inc.

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Indianapolis, IN 46256

www.wiley.com

Copyright 2007 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-11487-2

Library of Congress Cataloging-in-Publication Data:

Beginning XML / David Hunter ... [et al.]. 4th ed. p. cm.

ISBN 978-0-470-11487-2 (paper/website)

1. XML (Document markup language) I. Hunter, David, 1974 May 7-QA76.76.H94B439 2007

006.7'4--dc22

2007006580

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I would like to thank God, for continuing to give me opportunities to do what I love; my church family, for giving me more support than I deserve; and Andrea, for giving me more support than anyone deserves. I would also like to thank the editors, for their constant help.

Their dedication to the quality of this book was a major factor in its success. David

To Ali and Jude, for their loving patience. Jeff

To my two brothers, Peter and Stephen, who have both helped me in my life and career in their own ways, many thanks. Joe

To my wife, Catherine, and children, Deborah, David, Samuel, and Sarah, for their patience and support while I am busy writing books. Eric

To my late grandmother, Mona Cartledge, who once gave me a Commodore Pet. Danny

About the Authors

David Hunter is a Senior Technical Consultant for CGI, a full-service IT and business process services partner. Providing technical leadership and guidance for solving his clients' business problems, he is a jack-of-all-trades and master of some. With a career that has included design, development, support, training, writing, and other roles, he has had extensive experience building scalable, reliable, enterprise-class applications. David loves to peek under the hood at any new technology that comes his way, and when one catches his fancy, he really gets his hands dirty. He loves nothing more than sharing these technologies with others.

Jeff Rafter is an independent consultant based in Redlands, California. His focus is on emerging technology and web standards, including XML and validation. He currently works with Baobab Health Partnership with a focus on improving world health.

Joe Fawcett (http://joe.fawcett.name) started programming in the 1970s and worked briefly in IT when leaving full-time education. He then pursued a more checkered career before returning to software development in 1994. In 2003 he was awarded the title of Microsoft Most Valuable Professional in XML for community contributions and technical expertise; he has subsequently been re-awarded every year since. Joe currently works in London and is head of software development for FTC Kaplan Ltd., a leading international provider of accountancy and business training.

Eric van der Vlist is an independent consultant and trainer. His domains of expertise include web development and XML technologies. He is the creator and main editor of XMLfr.org, the main site dedicated to XML technologies in French, the lead author of Professional Web 2.0 Programming, the author of the O'Reilly animal books XML Schema and RELAX NG and a member or the ISO DSDL (, or meet him at one of the many conferences where he presents his projects.

Danny Ayers is a freelance developer and consultant specializing in cutting-edge web technologies. His blog (http://dannyayers.com) tends to feature material relating to the Semantic Web and/or cat photos.

Linda McKinnon has more than 10 years of experience as a successful trainer and network engineer, assisting both private and public enterprises in network architecture design, implementation, system administration, and RFP procurement. She is a renowned mentor and has published numerous Linux study guides for Wiley Press and Gearhead Press.

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Acknowledgments

This book would not have been possible without the work of the many developers dedicated to improving the Web through standards. We would also like to thank the countless contributors to mailing lists, IRC channels, forums, and friends that have helped us through the difficult corners of the specifications and technologies presented in this book.