A Ghost has been defined as the disembodied spirit or soul of a deceased person, although in popular usage the term refers only to the apparition of such a person. Often described as immaterial and partly transparent, ghosts are reported to haunt particular locations or people that they were associated with in life or at time of death.
Poltergeist (from German words poltern, meaning to make noise, and Geist, meaning "ghost" or "spirit"), or recurrent spontaneous psychokinesis (RSPK) denotes an ostensibly paranormal phenomenon attributed to an invisible spirit or ghost that manifests itself by moving and influencing objects, generally in a particular location such as a house or room or place within a house.
In religion and mythology, occultism and folklore, a demon (or daemon, daimon; from Greek δαίμων daimōn) is a supernatural being that is generally described as a malevolent spirit. In Ancient Near Eastern religions as well as in the derived Abrahamic traditions, including ancient and medieval Christian demonology, a demon is considered an "unclean spirit" which may cause demonic possession, to be addressed with an act of exorcism.
Poltergeist (from German words poltern, meaning to make noise, and Geist, meaning "ghost" or "spirit"), or recurrent spontaneous psychokinesis (RSPK) denotes an ostensibly paranormal phenomenon attributed to an invisible spirit or ghost that manifests itself by moving and influencing objects, generally in a particular location such as a house or room or place within a house.
In religion and mythology, occultism and folklore, a demon (or daemon, daimon; from Greek δαίμων daimōn) is a supernatural being that is generally described as a malevolent spirit. In Ancient Near Eastern religions as well as in the derived Abrahamic traditions, including ancient and medieval Christian demonology, a demon is considered an "unclean spirit" which may cause demonic possession, to be addressed with an act of exorcism.
Source: Wikipedia
