A ghost is considered to be the spirit of a dead person. Scientists say that there are no real ghosts, but many people believe that there are.
There are many stories about ghosts in books and movies. Sometimes the ghost is the spirit of a person who was killed or who died. The ghost may stay on Earth because he or she has unfinished problems or is still trying to say good bye to loved ones. Sometimes ghosts are said to live in a particular locality, for example an abandoned house.