This is a Packt Beginners Guide, which means it focuses on practical examples and has a fast-paced but friendly approach, with the opportunity to learn by experiment and play. Each chapter builds a practical plug-in from the ground up using step-by-step instructions. Individual sections show you how to code some functionality into your plug-in and follow up with a discussion of concepts. This book is for programmers working with WordPress, who want to develop custom plug-ins and to hack the code base. You need to be familiar with the basics of WordPress and PHP programming and believe that code is poetry; this book will handle the rest.