Ghosts are believed to be the apparitions of dead people. They appear the same as the person before her/his death, and are often encountered at places they were psychologically attached to in their lifetime. At times even devils and demons are referred to as them only. They are supposed to be the cause of haunting and of paranormal phenomena associated with a particular place or building. Such phenomena has been reported to manifest as apparitions, poltergeist disturbances, cold drafts, sounds of footsteps, voices, as well as various odors coming from no visible source in sight.