censorship, official prohibition or restriction of any type of expression believed to threaten the political, social, or moral order. It may be imposed by governmental authority, local or national, by a religious body, or occasionally by a powerful private group. It may be applied to the mails, speech, the press, the theater, dance, art, literature, photography, the cinema, radio, television, or computer networks. Censorship may be either preventive or punitive, according to whether it is exercised before or after the expression has been made public. In use since antiquity, the practice has been particularly thoroughgoing under autocratic and heavily centralized governments, from the Roman Empire to the totalitarian states of the 20th cent. Sections in this article:The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved. See more Encyclopedia articles on: Legal Terms and Concepts