Dreams have always been a mystery to people. Why do we have them? What do they mean?\nScientists have been searching for more than a century trying to figure out why people dream and what significance is behind the stories in our head while we sleep. Often, dreams contain some elements of our daily lives and recent events, but they take strange turns. Sometimes they\u2019re good. Sometimes they scare us.\nWhat Are Dreams?\nDreams are the images that pass through our minds while we sleep. They may be the result of random electrical stimuli, or they may have a larger purpose.\nScientists now know that while we sleep, the emotional part of our brain is highly active, which is why dreams are often vivid and intense. However, other parts of our brain are less active, which can make our dreams nonsensical.\nAlthough most often, we don\u2019t know what\u2019s happening when we sleep, sometimes we can have lucid dreams. This is when you realize you\u2019re in a dream and can control what\u2019s happening, while you\u2019re still asleep.\nWhen Do We Dream?\nDreaming happens during the fifth and deepest phase of sleep, rapid eye movement (REM). This stage can last for hours. Dreams can last anywhere from 5 to 20 minutes. You usually have many dreams every night, but probably forget most of them.\nDuring REM sleep, your body is in a completely relaxed, almost paralyzed state. Because of this,\u00a0you can\u2019t act out while dreaming and hurt yourself.\nWhy Do We Dream?\nThe clear answer to this question remains a mystery. Researchers have tried numerous studies watching people sleep while studying their brain activity. Current data is coming from websites where people share their dreams, such as dreamboard.com. But, for now, researchers have a range of theories about why we dream.\nSigmund Freud remains one of the most popular theorists about dreams. He believed that every dream has meaning and that those meanings were related to sexual longing.\nSince his research in 1900, others have suggested that dreams help us:\n\nCope with emotions\nSolve problems in our daily lives\nPlay a role in learning\n\nRegardless of their purpose, many artists, scientists, and everyday people have found long-sought answers, inspiration, and closure through dreaming.