Description Sleeping is something every human on Earth does, but why do we need to do it? Readers discover the answer in this accessible guide to the importance of sleep. Engaging color photographs and achievable text present the stages of sleep, the consequences of not getting enough sleep, and the benefits of getting the right amount of sleep each night. Glossary terms help readers navigate and process new concepts. Age-appropriate language makes this essential material easy to comprehend, giving readers a full understanding of this key ingredient to a healthy life.