According to Icelandic tradition, an Ærsladraug is a type of draug, a ghost that lives in a house and makes noise, moves things around, and causes various unexplained phenomena inside the building. Icelandic stories about such ghosts often describe them pinching and biting people, pushing them, throwing small objects, slamming doors, starting fires, and damaging electrical appliances. They are also associated with unexplained odors. Ærsladraugur are believed to attach themselves not to specific places, but to people, following them as they move. Stories of such ghosts have been found in Icelandic folklore since ancient times, although the word "Ærsladraugurinn" is relatively new, originally appearing as a translation of the title of Noël Coward's play "The Blithe Spirit", but later becoming used as an Icelandic equivalent of the German term poltergeist, which has become widespread throughout the world.