The Corporation for Public Broadcasting operates a nonprofit broadcast network that broadcasts noncommercial programming. Public television stations are locally licensed. Their broadcast lineup includes programming provided by the Public Broadcasting System (PBS) and shows that may be locally produced. Public television broadcasts programs it believes to be informative and of a high quality without any concern for the size of the audience it might attract.
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Commercial Television
Commercial television stations are owned by corporations or private citizens and may be bought and sold. They generate revenue by selling advertising. Their broadcast lineup consists of network programming, local programs like newscasts, and syndicated shows. Commercial television stations seek to broadcast programs that will attract a large audience, as the size of the audience determines the advertising rates that are charged.
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Networks
Public television receives its network programming from PBS. Commercial stations may be affiliates of ABC, NBC, CBS, Fox, or the CW, and receive programming from those networks. Stations receive local "avails," or commercial time, within a network program and may sell that air time to local advertisers.
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Independant Commercial Television Stations
Some commercial stations choose not to be affiliated with a network and are known as independent stations. Their broadcast lineup includes locally produced shows and syndicated programming.
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Revenue
Public television receives funding from the government and augments that with grants from corporations and donations from viewers. Commercial television stations derive revenue from the sale of commercials and ads sold on the station's website. Cable networks receive revenue from subscriptions generated by cable and satellite providers, along with advertising revenue.
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