Why do humans sleep and what happens during different sleep stages?

Humans sleep to rest their bodies and minds, just like how you rest after a long day at school.

Imagine your body is like a toy that needs charging, when you sleep, it gets all the energy back for tomorrow. Your brain also takes a little nap during sleep, so you can think clearly again.

There are different stages of sleep, like different levels of rest:

• In the first stage, your body starts slowing down, like when you're just sitting on the couch after a big lunch.
• Then you fall deeper into sleep, and your brain goes to work fixing things up, like how you tidy your room before going to bed.

After that, you enter deep sleep, where your body really rests and grows. It's like when you're fast asleep and don't even notice the noise around you.

Then comes dream time, when your brain is busy making up fun stories, just like when you imagine playing with your favorite toys while you’re drifting off to sleep.