We spend about 26 years of our lives sleeping, but how much do you really know about what happens when your head hits the pillow? This book answers all your questions about what goes on in your head when you snooze, including the difference between light and deep sleep, where dreams come from, and how essential sleep is to staying healthy. Discover fascinating facts about how people slept in the past, and how people sleep in different ways around the world. Did you know that the oldest mattress was found in South Africa and is 77,000 years old? Vivid illustrations by Vicky Woodgate bring the topic to life.