(from German poltern, meaning to rumble or make noise, and Geist, meaning "ghost", "spirit", or "embodiment") denotes a spirit or ghost that manifests itself by moving and influencing objects.
Hypotheses
Historically, several different hypotheses have been put forward to explain the poltergeist phenomenon.
Mischievous spirits
A pamphlet printed in London in 1698 by Mr. Ricard Chamberlain provides an account of a poltergeist-type haunting that had occurred some years before. Two copies of the pamphlet exist in the British Museum called: "Lithobolia, or stone throwing Devil. Being an Exact and True account (by way of Journal) of the various actions of infernal Spirits or (Devils Incarnate) Witches or both: and the great Disturbance and Amazement they gave to George Walton's family at a place called Great Island in the province of New Hampshire in New England, chiefly in throwing about (by an Invisible hand) Stones, Bricks, and Brick-Bats of all sizes, with several other things, as Ha
Source:
http://en.wikipedia.org/wiki/Poltergeist