As literary political fiction and dystopian science-fiction, Nineteen Eighty-Four is a classic novel in content, plot and style. Many of its terms and concepts, such as Big Brother, doublethink, thoughtcrime, Newspeak, Room 101, telescreen, 2 + 2 = 5, and memory hole, have entered into common use since its publication in 1949. Nineteen Eighty-Four popularised the adjective Orwellian, which describes official deception, secret surveillance and manipulation of recorded history by a totalitarian or authoritarian state.

(Source: Wikipedia)