Bluetooth devices use radio waves to connect. The radio waves come from a small computer chip. When one Bluetooth device comes close to another Bluetooth device, they send out radio signals to each other. It makes the things we do every day so much more convenient. No wires, cables, or cords, allows you to take computers, game controls, and many other objects from room to room. You can even call your friends from your cell phone while in your car and the sound will come out over the speakers, all thanks to Bluetooth technology! This book will allow students to use tools and materials to design and build a device that uses light or sound to solve the problem of communicating over a distance.