Why do we need to sleep

Question

Why do we need to sleep

Answer 1

for the body to rest and the mind to process the days activities and knowledge

Answer 2

so the body can rest and repair it self.

Answer 3

In addition to repairing the body, it also helps to stabilize moods.  Ever notice that you get cranky if you haven't gotten enough sleep?  

Answer 4

Researchers do not know exactly why people need sleep, but we do know that lack of sleep can kill. In research studies, rats normally live two to three years, but if rats are totally deprived of sleep, they only live about five weeks. They also develop sores, their immune systems do not work well and their body temperature drops. Humans deprived of sleep for long periods begin hallucinating and develop other mental problems.

I like to think about it like a computer (if you understand). As we mess around on the computer, moving files and adding/deleting stuff our hard drive (brain) because a bit of a jumbled mess. When you fall asleep your brain is able to shut down some areas and go back and repair (rearrange) some neurons and in some/most cases build more pathways. In essence your brain gets a make-over and upgrade when you sleep. Think of how complex a thing it really is? If you don't shut it down and fix the problems from time to time its destined to break.