Nicholas C. Zakas - Professional JavaScript for Web Developers

Professional JavaScript for Web Developers, Third Edition

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Copyright 2012 by John Wiley & Sons, Inc., Indianapolis, Indiana

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To my parents, who never cease to support and inspire me.

ABOUT THE AUTHOR

NICHOLAS C. ZAKAS has been working with the web for over a decade. During that time, he has worked both on corporate intranet applications used by some of the largest companies in the world and on large-scale consumer websites such as My Yahoo! and the Yahoo! homepage. As a presentation architect at Yahoo!, Nicholas guided front-end development and standards for some of the most-visited websites in the world. Nicholas is an established speaker and regularly gives talks at companies, conferences, and meetups regarding front-end best practices and new technology. He has authored several books, including Professional Ajax and High Performance JavaScript , and writes regularly on his blog at http://www.nczonline.net/ . Nicholass Twitter handle is @slicknet.

ABOUT THE TECHNICAL EDITOR

JOHN PELOQUIN is a front-end engineer with over ten years of JavaScript experience ranging across applications of all sizes. John earned his B.A. in mathematics from the University of California at Berkeley and is currently a lead developer for a health care startup where he makes use of the latest in front-end technologies. Prior to editing this volume, John edited JavaScript 24-Hour Trainer by Jeremy McPeak (Wiley, 2010). When he is not coding or collecting errata, John is often found engaged in mathematics, philosophy, or juggling.

CREDITS

EXECUTIVE EDITOR

Carol Long

SENIOR PROJECT EDITOR

Kevin Kent

TECHNICAL EDITOR

John Peloquin

PRODUCTION EDITOR

Kathleen Wisor

COPY EDITOR

Katherine Burt

EDITORIAL MANAGER

Mary Beth Wakefield

FREELANCER EDITORIAL MANAGER

Rosemarie Graham

ASSOCIATE DIRECTOR OF MARKETING

David Mayhew

MARKETING MANAGER

Ashley Zurcher

BUSINESS MANAGER

Amy Knies

PRODUCTION MANAGER

Tim Tate

VICE PRESIDENT AND EXECUTIVE GROUP PUBLISHER

Richard Swadley

VICE PRESIDENT AND EXECUTIVE PUBLISHER

Neil Edde

ASSOCIATE PUBLISHER

Jim Minatel

PROJECT COORDINATOR, COVER

Katie Crocker

PROOFREADER

Nicole Hirschman

INDEXER

Robert Swanson

COVER DESIGNER

LeAndra Young

COVER IMAGE

iStock/Andrew Rich

ACKNOWLEDGMENTS

EVEN THOUGH THE AUTHORS NAME is the one that graces the cover of a book, no book is the result of one persons efforts, and Id like to thank a few of the people involved in this one.

First and foremost, thanks to John Wiley & Sons for continuing to give me opportunities to write. They were the only people willing to take a risk on an unknown author for the first edition of Professional JavaScript for Web Developers , and for that I will be forever grateful.

Thanks to the staff of John Wiley & Sons, specifically Kevin Kent and John Peloquin, who both did an excellent job keeping me honest and dealing with my frequent changes to the book as I was writing.

Id also like to thank everyone who provided feedback on draft chapters of the book: Rob Friesel, Sergey Ilinsky, Dan Kielp, Peter-Paul Koch, Jeremy McPeak, Alex Petrescu, Dmitry Soshnikov, and Juriy Kangax Zaytsev. Your feedback made this book something that Im extremely proud of.

A special thanks to Brendan Eich for his corrections to the history of JavaScript included in Chapter 1.

Last, but certainly not least, thanks to Rey Bango for writing the foreword of this book. I had the pleasure of meeting Rey for the first time in 2010 after conversing online for several years. Hes one of the truly nice guys in the industry, and Im honored that he agreed to lend his time to this book.

FOREWORD

I look back at my career (now 20+ years), and in between coming to the realization that my gray hairs have really sprouted out, I reflect on the technologies and people that have dramatically affected my professional life and decisions. If I had to choose one technology, though, that has had the single biggest positive influence on me, it would be JavaScript. Mind you, I wasnt always a JavaScript believer. Like many, I looked at it as a play language relegated to doing rotating banners and sprinkling some interesting effects on pages. I was a server-side developer, and we didnt play with toy languages, damn it! But then something happened: Ajax.