Ghosts, in folklore, fiction and popular culture, are the souls of dead people who can make their presence known to the living. In some accounts, ghosts become visible, in others they remain invisible but are able to make their presence known in other ways. They are usually said to haunt a place or a person with which they were associated in life.
Belief in ghosts is widespread in many different cultures around the world. Most cultures have practiced some form of veneration of the dead, often as a way to appease spirits of the dead who might otherwise cause misfortune. Many religious practices, including exorcism and funeral rites have grown out of a belief that ghosts need to be placated.