Dreams are experiences that occur during sleep, often involving a series of thoughts, images, and sensations. They can be vivid and emotional, sometimes reflecting our daily lives, fears, or desires. Most dreams happen during the REM sleep stage, which is characterized by rapid eye movement and increased brain activity. Scientists believe that dreams may serve various purposes, such as processing emotions, consolidating memories, or problem-solving. While the exact reasons for dreaming are still not fully understood, many cultures throughout history have viewed dreams as significant, often interpreting them as messages or omens related to the subconscious mind.