Why do I dream?

I know almost nothing about psychology and the brain.

I’ve worked a lot the past few weeks and I’ve been very tired. I tend to fall asleep early. Yet, I have the most vivid dreams. In fact, I haven’t had such dreams in many years.

Has there ever been a reason determined for dreams?

no one really knows for sure why we dream,
some tell me that it is to aid sleep, your brain just naturally entertaining itself,

heres an interesting link from this garfield lady at the discovery channel

Why the heck do I dream?
im sure there are physiological explanations, stuff to do with REM and such, of which i am interested of also, but you may need to be a little more detailed with your question to get at that

by the way, i have noticed that the harder i work throughout the day, and the more tired i am in the evening, the more vivid my dreams become,

that’s gotta mean something

If it means something why aren’t they retained?

im not really sure what you’re asking me…

Actually, many doctors believe that have dreaming pretty much figured out. There was a lengthy article about it in SciAm some time ago. If I remember correctly, the consensus is that it is the brains method of processing and cementing memories and skills learned during the day.

I think it is the act of dreaming that is useful, not being able to remember what they are.