Freud believed dreams were the key to our unconscious minds and that probing them revealed the deepest secrets of our beings; there are neuroscientists today who think dreams have no meaning at all. The answer may lie somewhere in between. Some current researchers propose that dreams are the brain's way of rehearsing potentially harmful fight-or-flight situations. Others argue that they are a mechanism to sift through and organize memories. Dreams may be a means of emotional healing or simply the random firings of the sleeping brain.

Whatever the scientific reason, certain symbols appear again and again in across cultures and history. Human fascination with dreams began long before Freud. In the earliest surviving piece of literature, the Mesopotamian odyssey Epic of Gilgamesh, dreams are the way the Gods communicate their plans to human beings so they can act accordingly. The Ancient Egyptians thought dreams were prophetic, a belief passed on to the Ancient Greeks. Similarly, in Ancient China, it was thought that during dreams, one's soul could leave the body and learn about the future from the Gods and the souls of the departed. The Middle Ages in Europe saw creation of the the equivalent of today's dream dictionaries—written compendiums outlining dream symbols and their meanings.

What's incredible about those Medieval documents is that they reveal that people many hundreds of years ago had similar dreams to today. Since the images persist, its hard to imagine they don't contain some universal meaning. Susan Bergmann, a licensed social worker who works with the dream sharing and interpretation social media platform and App DreamsCloud, explains there's no single, definitive meaning for the symbols that occur in each of our dreams. However, she says, "Just as a smile usually means that someone is happy, these dream images are so common, that they do have a generally accepted meaning." And being able to interpret them can offer insight into issues in our waking lives that need attention.

There are hundreds of symbols and scenarios to explore and some are virtually universal. (Raise your hand if you have dreamed that you showed up for an exam completely unprepared). If you want to delve deeper into interpreting your dreams, many books can help, from Freud's classic, The Interpretation of Dreams to Dream Dictionary for Dummies. Here are a few symbols and situations to get started:

Falling

Whether you are careening off a cliff or tripping down the stairs, the loss of control that falling triggers can feel excruciatingly chaotic. You may feel like you are letting others or yourself down. However, author and dream expert Ian Wallace points out that falling in a dream can "bring you down to Earth" and release you from clinging to a stressful situation over which you have no control.

Animals

Dreams about animals point toward tapping into instinct over reason. Maybe you can gain information from getting in touch with a hidden need: is something holding you back? A relationship that needs work? A barrier to growth you might break down?

Cats

People have strong feelings about cats which will color their meaning in a dream. Was the cat a loving pet? It might represent a family member or close friend. If you dream of a feral cat, it could represent a part of yourself that you need to gain control of.

Bears

Traditionally bears signify renewal and change. However, if you are being chased by a bear, you might feel anxious about a threatening situation or overbearing relationship.

Horses

Like the animal itself, a dream of horses can stand for something which or someone whom represents strength, endurance, and power. Running horses are an expression of energy and freedom or a desire for such freedom.

Dogs

For many, dogs are the most loyal and trustworthy animal. What is the dog doing in your dream? That might be a message about what you need more of in your own life.

Snakes

Dreaming about snakes is fairly common. Dream expert Barbara Condron explains snake imagery as representing the "dreamer's creative urge toward wisdom." Other details in the dream may provide clues to the area where you are seeking to learn some truth: be it in the realm of the spiritual, emotional, physical, or intellectual. Of course, our culture also sees snakes as frightening—symbols in dreams are all about personal context.

Flying

Dreams of being able to fly are often one of the most euphoric to experience. You are happy, hopeful and may wake up with a sense mastery (if you remember...). On the flip side, you might be experiencing limitations in your daily life and yearn for freedom and achievement.

Being Chased

Do you feel threatened by something? Jungian psychotherapist Richard Nicoletti says this type of dream is universal. He points out that who is chasing you matters. Is it a person or something abstract such as darkness? He adds that your unconscious is telling you that you are avoiding something fearful or difficult and you need to face the issue or person to help find a resolution.

Suffocation

Another unpleasant dream that, like falling, you can almost feel while you sleep. Suffocation is a warning. You feel smothered by something in your life, another person or situation, and you need to take action to protect yourself. It can literally be a wake up call: some people who suffer from sleep apnea dream of suffocating, their body's way of telling them that they desperately need air.

Babies

Babies are vulnerable and needy. A baby in a dream can symbolize a part of yourself that requires more care and nurturing or something from your past that you should revisit. Do you need to take better care of yourself? Or do you crave more from a relationship? Of course, if you are a parent, the baby might symbolize your own child. Some dream experts say dreaming of a baby can be a very early sign that you are pregnant, another example of the mind body connection.

Losing Teeth

Having your teeth crumble and fall out of your mouth might indicate there is something in your waking life that's causing you to lose confidence. You might also be worried about illness or physical decline.

Water

Dreaming about a water is common across cultures and throughout history. Think about the context and your own relationship to water. Is it turbulent or smooth? Are you afraid of water or does it give you a sense of peace? Psychotherapist Jeffrey Sumber says water can also symbolize purification, change, and even transcendence.

Death

While dying in a dream can feel terrifying, it may signify the end of one stage of life and emerging into another. Dream expert Lauri Loewenberg says that children sometimes have dreams about dying when they reach a particular milestone such as going to kindergarten or learning how to ride a bike.

Naked in Public

Nudity is a sign of feeling vulnerable. It may indicate a fear of having your faults exposed. However, if you are comfortable with being naked in your dream, you might be proud of an accomplishment or even feel sexually confident.

If anyone has useful insight into your dreams, it is probably you. To remember them more vividly, it is helpful to keep a journal and write them down as soon as you wake up. Notice the emotions and thoughts that arise as you think about the images and stories your dreams spin.

T. M. Lurhmann is a professor of Anthropology at Stanford University who studies the ways different cultures connect to the idea of "spirit" and suggests there could be a profound benefit to staying in tune with our dreams. Some people of faith, such as groups he's worked with in Ghana and India still believe that dreams are sacred, a way that God speaks to them. On the other end of the spectrum, he has interviewed evangelical Christian Americans who think that the wild imaginings they encounter deep in the night are the mundane result of "sleep deprivation." His work led him to record his own dreams and seek their meaning. "After that," he wrote, "My dream life changed. I seemed to dream more. I remembered more detail. I sometimes had dreams of mythic intensity." He concluded, "It seems likely that the way our culture invites us to pay attention to that delicate space in which one trembles on the edge of sleep changes what we remember of it."