I stood outside my house on a sunny morning. It seemed like a normal day. Then hundreds of snakes started slithering toward me! I ran to my family’s car, which was parked in the driveway. The car was locked, so I climbed onto the hood.

    But the snakes began climbing the sides of the car. They came closer . . . and closer . . .

    And then . . . I woke up. 

    All human beings (and many animals) have dreams. Some dreams, like my snake nightmare, are scary. Some dreams let you live out fantasies. (Maybe you’ve fought bad guys with the Avengers or danced onstage with Sabrina Carpenter.) Other dreams—like the one where you show up to school in your underwear—are just plain weird.

    But what exactly are dreams? And why do we have them?

    Humans have been asking these questions for thousands of years. Now, thanks to science, we are starting to find some answers.

    I stood outside my house one morning. It seemed like a normal day. Then hundreds of snakes started slithering toward me! I ran to my family’s car. It was parked in the driveway. It was locked. So I climbed onto the hood.

    But the snakes climbed up the sides of the car. They came closer . . . and closer . . .

    And then . . . I woke up.

    All human beings have dreams. Many animals dream too. Some dreams are scary, like my snake nightmare. Some dreams are fantasies. (Maybe you’ve fought bad guys with the Avengers.) Other dreams are weird, like the one where you show up to school in your underwear.

    But what exactly are dreams? And why do we have them?

    I stood outside my house on a sunny morning. It seemed like a normal day—but then hundreds of snakes started slithering toward me! I ran to my family’s car, which was parked in the driveway. The car was locked, so I climbed onto the hood.

    But the snakes began climbing the sides of the car. They came closer . . . and closer . . .

    And then I woke up.

    All human beings have dreams, and many animals do too. Some dreams, such as my snake nightmare, are scary. Some dreams allow you to live out fantasies, like fighting bad guys with the Avengers or dancing onstage with Sabrina Carpenter. Other dreams—like the one where you show up to school in your underwear—are just plain weird.

    But what exactly are dreams? And why do we have them?

    Humans have been asking these questions for thousands of years—and now, with the help of science, we’re beginning to uncover some answers.

    A long, long time ago, some people believed that dreams were messages from the gods. Some thought they were a way of seeing the future. Others believed that nightmares were sent by the devil. 

    But not everyone in the distant past thought dreams were supernatural. Aristotle was a famous writer and thinker in ancient Greece. He described dreaming as “thinking while we sleep.” Today, more than 2,000 years later, many scientists agree with him.

    We now know that during the night, the body goes through stages of sleep. Most dreaming happens during the stage of sleep known as REM. That stands for rapid eye movement. During this stage, your eyes move around. Your breathing and heart rate get faster.

    Long ago, some people believed that dreams were messages from the gods. Some thought they were a way to see the future. Others said nightmares were sent by the devil.

    But not everyone back then thought dreams were supernatural. Aristotle was a famous writer and thinker in ancient Greece. He described dreaming as “thinking while we sleep.” That was more than 2,000 years ago. Today many scientists agree with him.

    We now know there are stages of sleep. Most dreams happen during the REM stage. (REM stands for rapid eye movement.) During this stage, your eyes move around. You breathe faster. Your heart rate goes up.

    Long ago, some people believed that dreams were messages from the gods, while others thought they were a way of seeing the future. And some believed that nightmares were sent by the devil.

    But not everyone in the distant past thought dreams were supernatural. Aristotle, a famous writer and thinker in ancient Greece, described dreaming as “thinking while we sleep.” Today, more than 2,000 years later, many scientists agree with him.

    We now know that during the night, the body goes through stages of sleep. Most dreaming happens during the stage of sleep known as REM, which stands for rapid eye movement. During this stage, your eyes move around and your breathing and heart rate get faster.

    But what’s happening in your brain during REM? When you’re awake, certain areas of your brain are in control. These parts of your brain help you solve math problems. They allow you to say hello to a friend. They make you duck when a basketball comes flying at your head. 

    When you are asleep, there are no math problems to solve. There are no friends to greet. There are no basketballs to dodge. Your brain uses this quiet time to go through the information it collected while you were awake. That includes thoughts, memories, and feelings.

    As you sleep, different areas of your brain take control. 

    These areas are associated with emotions and memory. They work together to create stories—or dreams. The settings and characters come from your memories.

   When you’re awake, certain areas of your brain are in control. These parts help you solve math problems. They allow you to say hi to a friend. They make you duck when a basketball flies toward you.

    But when you’re asleep, there are no math problems to solve. There are no friends to greet. There are no basketballs to dodge. Your brain uses this quiet time to go through the information it collected while you were awake. That includes thoughts, memories, and feelings.

    As you sleep, different areas of your brain take control.  These areas are associated with emotions and memory. They work together to create stories—or dreams. The settings and characters come from your memories.

    But what’s happening in your brain during REM? When you’re awake, certain areas of your brain are in control. These parts of your brain help you solve math problems, allow you to say hello to a friend, and make you duck when a basketball suddenly comes flying at your head.

    When you are asleep, there are no math problems to solve, no friends to greet, and no rogue basketballs to dodge. Your brain uses this quiet time to go through the information it collected while you were awake, including thoughts, memories, and feelings.

    When you’re sleeping, different areas of your brain take control. These areas, which are associated with emotions and memory, work together to create stories—or dreams. The settings and characters come from your memories.

    Today we understand that dreams come from our brains. But one question remains. Why do we dream at all?

    Some scientists believe that dreams help us figure out how to react in certain situations. For example, my snake nightmare could have been practice for scary situations in the real world.

    Other experts believe that dreams help us sort out our emotions. Maybe I was feeling worried about something. My dream could have been a way of facing that.

    Still others think that dreaming helps our brain organize memories. We keep some and get rid of others. That way our brains don’t get too cluttered.

    What most researchers agree on is that our dreams are about us—our joys, our worries. “Dreams are our most personal creations,” said scientist Stephen LaBerge. “They are colored by who we are—and who we could become.” 

    Today we know that dreams come from our brains. But why do we dream?

    Some scientists say dreaming helps us figure out how to react in certain situations. Think of my snake nightmare. Maybe it was practice for scary situations in the real world.

    Others say dreaming helps us sort out our emotions. Maybe I was worried about something. My dream could have been a way of facing that.

    Still others say dreaming helps our brain organize memories. We keep some and get rid of others. That way our brains don’t get too cluttered.

    But most experts agree that our dreams are about us—our joys, our worries. “Dreams are our most personal creations,” said scientist Stephen LaBerge. “They are colored by who we are—and who we could become.” 

    Today we understand that dreams come from our brains. Still, one question remains. Why do we dream at all?

    Some scientists believe that dreams help us figure out how to react in certain types of situations—for example, my snake nightmare could have been practice for scary situations in the real world.

    Other experts believe that dreams help us process our emotions. Maybe I was feeling worried about something, and my dream was a way of confronting that worry.

    Still others think that dreaming helps our brain organize memories, keeping some and discarding others so that our brains don’t
become overly cluttered.

    What most researchers agree on is that our dreams are about us—our joys, our worries, and so on. “Dreams are our most personal creations,” stated scientist Stephen LaBerge. “They are colored by who we are—and who we could become.”