Adam Trachtenberg is the senior manager of Platform Evangelism at eBay, where he preaches the gospel of the eBay platform to developers and businessmen around the globe. Before eBay, Trachtenberg co-founded and served as vice president for development at two companies, Student.Com and TVGrid.Com. At both firms, he led the front- and middle-end web site design and development. Trachtenberg began using PHP in 1997, and is the author of Upgrading to PHP 5 and coauthor of PHP Cookbook, both published by O'Reilly Media. He lives in San Francisco, California, and has a B.A. and M.B.A. from Columbia University.