The microcontroller unit (MCU) is the ultimate electronics tinker-toy, and in this book you’re going to see how to tinker away with it to your heart’s delight! My intended audience for this book is those who like to learn hands-on. Learning by doing and seeing has always been my preferred way to learn: If it’s yours too, let’s take the ride together. For those who like to understand the “why” first of all, the book also includes some background material that explains why using microcontrollers in everyday situations can be such a powerful concept. My only assumption is that you have some very basic knowledge.