Because dreams can sometimes be strange, complicated and surreal they have even been compared to hallucinations. A dream is an extension of one's imagination. This goes on to explain that whether we are awake or asleep our brains continually remain active. While asleep our subconscious dominates, allowing us to not only view our dreams but also enabling us to remember some of them. According to this theory dreams are the finished product of the chaos we life in.
Dreams are our subconscious making sense of both the physical world and the subconscious world.
Dreams not only help shape our lives but also are shaped by our lives which gives them a sort of mystical quality. Keeping this theory in mind may help explain why we dream. It may be that dreams are our minds wondering off in whichever direction they wish. Since we are asleep we relinquish our power and sort of activate auto-pilot. It may be that our dreams serve to make sense of the loads and loads of information we absorb throughout the day.