John Earl Clark holds a Master’s Degree in Human Computer Interaction from Georgia Tech and an undergraduate degree in Music Engineering from Georgia State University. John and his co-author, Bryan Johnson, worked together at MindSpring and later EarthLink, starting out in Technical Support and Documentation, before moving into Application Development and finally management of a small development team. After leaving Earthlink in 2002, John began working independently as a consultant and programmer, before starting Twelve Foot Guru, LLC with Bryan in 2005. John has been working with Sencha Touch since the first early beta releases. He has also worked with Sencha’s ExtJS since the early days when it was still known as YUI-Ext. John's first book with Bryan Johnson was called “Sencha Touch Mobile JavaScript Framework” and he is currently finishing up a new book called Sencha Touch Hotshots When he is not buried in code, John spends his time woodworking, playing guitar and brewing his own beer.