Some supernatural presence which frequents a place or attaches or periodically manifests to a particular person is said to be haunted. The agents involved are usually considered to include discarnate humans, termed ghosts or shades; discarnate animals; disembodied non-human spirits including poltergeists, and various spooks, phantoms, spectres or apparitions. Other classes of haunters include revenants who have returned from the dead, and in modern folk-lore, ectoplasmic or astral projections from living persons and extra-terrestrials or extra-dimensionals. Hauntings may be experienced through conventional means of knowledge so that they may be sensed as tactile, for example, clammy cold touches; olfactory, with stenches, perfumes or other odours; auditory, as musical vocal or mechanical sounds, and visually, by seeing the agent itself or its effects such as displaced objects, movement of drapery or doors, deposits or manifestations of articles, or other creativeness or destructiveness. Other experiences of hauntings may be through the emotions such as feelings of depression, dread and terror, although positive feelings like warmth, love and inspiration may also be produced.