Abstract Sleep is very important for our body to continue functioning normally and healthily. Approximately 1/3 of human life is spent asleep. Sleep, which has such a big place in our lives, is very important and necessary for life. Sleep is divided into two main stages: REM (Rapid Eye Movements) and Non-REM (Non-Rapid Eye Movements) sleep. During night sleep, REM and NREM phases alternate in a cycle. The quality, length and depth of sleep are very important for quality of life, fitness, functionality and for the body to continue in a healthy cycle. Many factors affect the length and quality of night sleep. Poor quality and irregularity of sleep invites sleep disorders and many sleep-related problems. This study aimed to compile the literature and provide a general review on sleep and sleep disorders. Keywords: Sleep, Sleep Disorders, Review