IN THIS CHAPTER
Discovering what a circuit is
Getting familiar with GPIO
Coming to grips with a soldering iron
Looking at ready-made add-on boards
Part 5 of this book deals with what is known as physical computing, or making your program reach out beyond the confines of keyboard and screen and into the physical world. You discover how you can use your Scratch and Python programming skills to sense what is happening in the outside world and to control lights, motors, and, in fact, anything else that uses electricity. However, before you can do this safely, without risking damage to you or your Pi, you need to look at a little bit of background electrical theory so that you have a foundation to build on.
In this chapter, we show you the relevant concepts that allow you to understand why the projects look like they do and what you should avoid doing. Next, we introduce you to the concept of GPIO connections, explain what they are, and look at why they are included in the Raspberry Pi computer. We also discuss in general how you can use them.