Network television

A television network is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay television providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small number of broadcast networks. Many early television networks (such as the BBC, NBC or CBC) evolved from earlier radio networks.

In countries where most networks broadcast identical, centrally originated content to all of their stations and where most individual television transmitters therefore operate only as large "repeater stations", the terms "television network", "television channel" (a numeric identifier or radio frequency) and "television station" have become mostly interchangeable in everyday language, with professionals in television-related occupations continuing to make a differentiation between them. Within the industry, a tiering is sometimes created among groups of networks based on whether their programming is simultaneously originated from a central point, and whether the network master control has the technical and administrative capability to take over the programming of their affiliates in real-time when it deems this necessary – the most common example being during national breaking news events.

In North America in particular, many television networks available via cable and satellite television are branded as "channels" because they are somewhat different from traditional networks in the sense defined above, as they are singular operations – they have no affiliates or component stations, but instead are distributed to the public via cable or direct-broadcast satellite providers. Such networks are commonly referred to by terms such as "specialty channels" in Canada or "cable networks" in the U.S.

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