Channel 4 is a British public-service television broadcaster that began transmission on 2 November 1982. Although largely commercially self-funded, it is ultimately publicly owned; originally a subsidiary of the Independent Broadcasting Authority (IBA), the station is now owned and operated by Channel Four Television Corporation, a public corporation of the Department for Culture, Media & Sport, which was established in 1990 and came into operation in 1993. With the conversion of the Wenvoe transmitter group in Wales to digital on 31 March 2010, Channel 4 became a UK-wide TV channel for the first time.

The channel was established to provide a fourth television service to the United Kingdom in addition to the licence-funded BBC's two services, BBC One and BBC Two and the single commercial broadcasting network, ITV.

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