Why do we dream? What they mean?

Have you ever thought why do we dream?

What really goes inside our brain when we dream.

The scientific study of dreaming is called ONEIROLOGY and for most of history it doesn't really exist because we can't hold on to our dreams , there are no measurements for it, you can't smell a dream , taste it. You really can,t tell about any other's dream and if you ask people what they dreamnt the results are almost unrealiable and infact its estimated that we forget 95% of the dream we have in first 10 minutes.

electrical activity in brain at certain stage of sleeping

Then in 1952 something amazing happened , researchers at the university of chicago  found some unique kind of electrical activity that occurs during a certain stage of person's sleeping. When researchers awoke people during this stage almost all of them had reported that they had been dreaming. ALSO, at the same time , during this stage the person's eyeballs were going crazy rapidly darting all over the place underneath their eyelids. You can actually this happening.

REM SLEEP(rapid eye movement).

During REM sleep bizzare stuff happens, if you look the electrical activity of a brain, it almost exactly mimics the way the brain acts when it's awake. The biggest difference being that the production of chemicals inside the brain like norepinephrine, serotonin and histamine is almost completely blocked, and that causes muscles to stop moving which is why you can dream about flying or running around , fighting ninjas but your body doesn't move.

It is possible to wake up and not being able to move your body because you are in REM atopia. You're completely conscious and know that you are awake but your body is not rrady to move on the other hand you can also be inside a dream and know that you are dreaming , this phenomenon is known as LUCID DREAMING. 

Back to REM , it was found that if you do something new the electrical activity of your brain shows variations and when the person sleeps the brain again try to recreate those electrical activity  in the unconsious part of the brain so that it helps us in future whether you learn that thing or not .  When the  impulses are detected by our consious part of the Brain our cortex freaks out  and doesn't know what it means so it tries it best creating a cohesive story thus forming a DREAM. This explains why our dreaming are so fantastic and completely random, they are not supposed to make sense , they are not the actual message from our brain.