This book is written for Arduino users of all stripes, from energetic newcomers to seasoned professionals. You already know what an Arduino is, and you have some ideas about what it can accomplish for you. You most likely already own one or have access to one. These are not requirements, just guesses. Your interest in Arduino and its inner mysteries is enough.
We don't have to spend any time going over the very basics here; introductory Arduino tutorials are everywhere. This book both covers a lot of ground in depth and hopes to follow you on your journey; it's not meant ot be discarded and useless after you blink your first LED.