REM sleep

REM sleep is when our brain is working really hard, but our body is taking it easy. It stands for "Rapid Eye Movement" and it happens when we are in a deep sleep.

When we are in REM sleep our eyes move quickly back and forth behind our eyelids, that is why it is called Rapid Eye Movement.

During this stage of sleep, our brain is super active and we often have vivid dreams. Our body also becomes very still, almost like we are frozen, so that we don't act out our dreams.

REM sleep is very important for our health because it helps us to feel well-rested and refreshed when we wake up in the morning.