There are 4 stages of sleep: Stage 1, Stage 2, Slow wave sleep, and REM. The stages occur in that order. Stage 1 occurs as you are falling asleep, and REM occurs last and contains the craziest...
Stage 1 is light sleep where you drift in and out of sleep and can be awakened easily. In this stage, the eyes move slowly and muscle activity slows. During this stage, many people experience sudden...