Ghost

In his Dictionary of occult sciences, Julien Tondrian gives for the term ghost the following definition: "materialization of the spirit of a dead, visible but intangible, also called a spectre. The popular tradition represents it as a skeleton covered with a shroud, sometimes dragging chains, and is in haunted castles (especially in Scotland!). They are usually suffering souls of murdered and they may announce a future death". In fact, there are two kinds of ghosts: the first is harmless ghosts whose return to earth has only one purpose, to redeem a fault to find peace and eternal rest, and often why they need the complicity of a living to help them achieve their mission on earth (but it may also be unknown to him). The second category is more worrying, since these ghosts return to get revenge, often as a result of the crime they have suffered, for cons, it should be realized that in such cases, there were no need in human and they are doing perfectly well alone! The theme of the ghost exists in practically all civilizations thus do we find traces in the writings of some ancient epic poets (Plato, Homer, Seneca the Younger) and the traditions of different countries: the Arab countries (Arabian Nights), the Celtic countries (the banshee), the Asian countries (Yūrei = 幽 霊, in Japan, Gwishin = 귀신, in Korea, Phi = ผี, in Thailand or Guǐ = 鬼, in China), but it is obviously in England and Scotland where we can find examples that have marked the most the popular mind (Hamlet, Sweet William's Ghost, The Unquiet Grave, A Christmas Carol ...).
Note that a ghost is also known as Poltergeist if it is responsible for disturbances such as loud noises or objects thrown around.