We often find that what we have read at night, after a night’s sleep, but remember more clearly and firmly. Could it be that sleep is a magical hand that helps us remember? The human brain must go through a series of processes when storing the necessary memory information, and dreams are the embodiment of one of the key processes. A scientist named Crick also proposed the idea of “dreaming is organizing memory”. The human brain is able to process a large amount of information that cannot be processed by electronic computers, discarding unnecessary information to organize the fragments of memory. “Dreams are simply a way for the human body to clear the brain’s thinking files.” The result is a number of fragmented pieces of thought that are grouped into storage cabinets and put in their proper place,” describes Stiegold. We dream with blinking eyes while we sleep, and these bizarre, misplaced and fragmented dreams that we have late at night are exactly what our brain is looking for in its ‘mutual index’.” Dreams act like our personal secretaries, organizing our memories effectively. Freud advocated that real memories, events and related emotional experiences must be “condensed” and “replaced” before entering the dream state. The source of memory varies according to the period of sleep. The situational memory components that make up dream elements are more likely to come from sleep onset or awakening after slow-wave sleep, while ordinary semantic memory resources are more abundant and vivid during fast-wave sleep. If not, the brain would become a completely indistinguishable bucket of information, like a malfunctioning robot that makes errors of judgment in doing things.