When we sleep our bodies may be at rest, but our brains are still at work. This is when we dream.
Whether you remember your dreams or not, we all dream every night during the deepest level of sleep, called Rapid Eye Movement (Rem). With 95 per cent of all thought being unconscious, dreaming uses up more of our brains than you think.
Understanding these dreams can help us understand ourselves better, according to most psychologists.
People have assigned meaning to dreams as far back as Biblical days - there are numerous references to dreams in the Bible. In those days, dreams were often seen as predictions of the future.
However, modern dream analysis stems from Sigmund Freud, the father of modern psychology, who said dreams are a reflection of our desires.
In children, this is straightforward: a boy sees a video game he wants and that night, dreams he is one of the characters. In adults, dream interpretation is more complicated because they draw in thoughts stored in our unconscious minds for years.
Today there are many competing theories about how we should interpret dreams, but few disagree dreaming represents our personal, underlying thoughts.
Sometimes dream interpretation is used in therapy to help people overcome painful memories.
There are also many so-called dream dictionaries, which assign meaning to a long list of symbols that pop up in dreams. However, these have little or no scientific basis and often come from myths or folklore.
Furthermore, everyone has a different way of interpreting the same object: a horse can mean one thing to a jockey, and something else to a person whose friend was killed in a riding accident. A psychologist might ask you to explore your thoughts surrounding the images in a dream.
If you are curious about exploring the meaning of your dreams, the first step is to keep a dream log. If you never remember your dreams, according to the International Association for the Study of Dreams (IASD), you should remind yourself to remember your dream right before you fall asleep. As you wake up, recall images that first come to mind, and write them down.
Pick up some books on dream interpretation. Here are some of the most widely respected dream scholars, according to the IASD: Deirdre Barrett, Mark Blagrove, Robert Hoss and Harry Wilmer.