Some ghosts are believed by some people to be the unhappy and often harmful spirit of a dead person. Once, many superstitious people believed in ghosts. As more persons became educated, the belief in ghosts still persists in parts of the world. There are many different ideas about the powers of a ghost. Some people insist that a ghost can be heard, but never seen. Others believe that ghosts are visible to some people and can be recognized because they never cast shadows or leave footprints, and can walk thru closed doors and solid walls. Believers in ghosts think that some evil causes ghosts exists to right and wrong or revenge a crime. For instance, they think that the spirit of someone who was murdered will return and causes trouble for the killer. This association with crime causes many to fear the possibility of ghosts. Ghosts are supposed to work only at night when the light is poor.
A person's senses can play tricks on him when it is difficult to see. A fluttering rag, reflected moonlight, or a white stone, may have led superstitious people to believe that they had seen a ghost. Animal movements, shutters slamming in the wind, or creaking doors also lead people to believe in ghosts. Ghosts play apart in many primitive religions. They have always been a favorite subject of writers and storytellers. Shakespeare created several famous ones in his tragedies, particularly in "Hamlet and Macbeth". Marley's ghost in "Dicken's A Christmas Carol" is a well-known literary figure.