The number one bestselling programming book is back with updated and expanded coverage of the newest release of "WoW!" "World of Warcraft (WoW)" is currently the world's largest massively multiplayer online role-playing game. The newest release, "Wrath of the Lich King," has created a demand for updated information on writing addons. This eagerly anticipated edition answers that request and is an essential reference for creating WoW addons. Written by a duo of authors who have each contributed a number of successful WoW addons, the book offers an overview of Lua and XML (the programming languages used to write addons) and includes coverage of specific pitfalls and common programming mistakes - and how to avoid them. Valuable examples show you detailed aspects of writing addons for WoW and demonstrate how to implement addon concepts such as variables, slash commands, secure templates, and more. "World of Warcraft" insiders share their techniques for writing addons for both the latest version of WoW as well as the new "Wrath of the Lich King" expansion set. This title guides you through the specific nuances of the WoW API with the use of detailed examples; discusses ways to distribute and host your WoW addons so others can download and use them; and, explains how to respond to events, create frames, and use the WoW API to interact with the game. You'll be well on your way to creating exciting WoW addons with this comprehensive reference by your side.