As defined by C. Wright Mills in The Power Elite (1956), the mass media have two important sociological characteristics: first, very few people can communicate to a great number; and, second, the audience has no effective way of answering back. Mass communication is by definition a one-way process. Media organizations are bureaucratic and (except in societies where all media are state-controlled) corporate in nature. Media output is regulated by governments everywhere, but the restrictions vary from very light advisory regulation (for example no cigarette advertising or nudity on TV), to the most comprehensive forms of censorship in totalitarian societies.