"The Internet of Things" is the new buzzphrase, but what is it? A toaster that texts? The fitness band on your wrist? The camera in an infant's room? Sure, it's all of those things. But it's also your phone: an ultra-sophisticated sensor and communications system in your pocket or purse—capable of tracking your steps, capturing an image, or calling an Uber. And it is actually not hard or expensive to make a sensing, communicating object yourself. Doing so can be rewarding, fun, and even useful. This book teaches the basics of building sensors and communicating objects through a series of practical, demonstrative, and fun activities.