Broadcast media originated with the development of the radio in the twentieth century. Prior to the radio, news and other information was transmitted across telegraphs and, later, telephones, but both technologies transferred information from one party to another. Radio allowed for information transfer from one party to multiple parties and, just as importantly, freed information transmission from physical wires. Radio was in its infancy prior to World War I, and governmental restrictions during the war prevented its rapid expansion. After the war, the development of radio technology increased quickly although programming remained limited. During the 1920s the US government developed guidelines and regulation for radio broadcasting that influenced the development of NBC and CBS.
By the 1930s radio had become well established as a medium for entertainment and information. By 1946 NBC, CBS and an emergent ABC (formed from a court-mandated division of NBC similar to NBC’s formation from a court-mandated division of AT&T’s radio and telephone operations) began regular television broadcasts, including newscasts that were generally ten to fifteen minutes in length. Although slow at first, the acceptance of television increased rapidly during the boom of the 1950s, and television ultimately replaced radio as the chief source of in-home entertainment by 1960.
Edward R. Murrow laid the foundation for modern television newscasts on CBS with the first program featuring simultaneous transmission coast-to-coast. Newscasts in the 1960s expanded to half-hour programs, and included The Huntley-Brinkley Report on NBC (later the NBC Nightly News) and the CBS Evening News with Walter Cronkite. Color television, first introduced in the 1950s, spread slowly both because of the associated production costs, and because many people who had first purchased black and white televisions sets were slow to transition – based in part on the limited availability of color programming. Cable television expanded the possibilities for broadcast media, and in 1980 Ted Turner launched CNN, the first 24-hour news channel. It has since been followed by numerous other networks devoted entirely to news broadcasts.