You might not have dreams as dramatic as A Nightmare On Elm Street. But when it comes to dreams, everybody has a mystical experience to share.
Some say they have foreseen the future in their dreams. Others have recurring dreams with bizarre themes - such as losing one's teeth or being chased by animals.
So is it merely coincidence when events in real life match a dream we've had? Or are dreams, as the ancient Greeks believed, revelations from the divine?
Scientists like Tso Wung-wai, an adjunct professor at the Chinese University of Hong Kong, believe that dreams are mostly images absorbed by our minds, which act as a warehouse of information during the day.
'Dreams are like videotapes and the retrieval system operates randomly,' said Professor Tso, who is convenor of the Study Group of Unexplained Phenomena.
Many people, when they set foot in a new place, claim they have been there before in their dreams.