Dreams are a communication of body, mind and spirit in a symbolic communicative environmental state of being. That's it! Now that you are thoroughly confused let me explain in a more down to earth language. Our brains are in constant activity. Different states of consciousness (like awake, asleep, alert, drowsy, excited, bored, concentrating or daydreaming) cause different brain wave activity. Our conscious mind, or the part we think with, our "window" into life, only takes up a very small portion of our brain activity. (some say this is only 10%) Other areas control things like breathing, heartbeat, converting light to vision, sound to hearing, balance when we walk, etc. etc. This too has it's own percentage (small). Another area controls imagination. This area is widely an undiscovered frontier. Imagination is more then dreaming of a new car or picturing someone with their cloths off! When you look at clouds and see shapes, or wood grain and see images, this is the "order from chaos" part of your imagination. The mind cannot deal with chaos very well, in fact it will resist it and sometimes manufacture order. (very important to the dreaming process.)This too occupies a small percentage of brian activity. Then there is memory. Memory is vast! And I believe it occupies more of the brains resources then most people believe.

And then there is the activity called dreaming. I think that to a certain extent, we dream all the time. Even while awake! But the process is functioning in our subconscious mind, out of view from our "window". If defined precisely, they may not be referred to as dreams technically, but the activity is very closely related. During certain cycles of brain activity while asleep, we can "view" these dreams with our conscious mind and record them in our memory. (this is why we sometimes remember them).