Broadcast television

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Broadcast television
The United States has a decentralized, market-oriented television system. Unlike many other countries, the United States has no national broadcast programming service. Instead, local media markets have their own television stations, www.dvdsetau.com which may be affiliated with or owned and operated by a TV network. Stations may sign affiliation agreements with one of the national networks. Except in very small markets with few stations, affiliation agreements are usually exclusive: If a station is an NBC affiliate, the station www.dvdsetau.com would not air programs from ABC, CBS or other networks.However, to ensure local presences in television broadcasting, federal law restricts the amount of network programming local stations can run. Until the 1970s and '80s, local stations supplemented network programming with a good deal of their own produced shows. Today, however, many stations www.dvdsetau.com produce only local news shows. They fill the rest of their schedule with syndicated shows, or material produced independently and sold to individual stations in each local market..The five major U.S. networks are NBC, CBS, ABC, Fox, and The CW. The first three www.dvdsetau.com began as radio networks: NBC and CBS in the 1920's, and ABC was spun off from NBC in 1943. Fox is a relative newcomer which began in 1986. The CW was created in 2006 when UPN merged with The WB www.dvdsetau.com.