Since World War II (1939–45) television—TV—has dominated American popular culture. From the moment of its arrival, TV redefined the way Americans spent their leisure time. In the twenty-first century, TV is the main media outlet for news, sports, entertainment, and politics. The industry is run by multi-billion-dollar corporations. Politicians, celebrities, sports promoters, and the film and music industries compete for the best TV coverage. Advertisers pay millions of dollars each year to promote their products during the most popular shows. From sports to news, from game shows (see entry under 1950s—TV and Radio in volume 3) to comedy, drama, and documentaries, TV offers something for almost everyone.

Although the principles of TV were established in the 1880s, it was not until 1924 that British inventor John Logie Baird (1888–1946) transmitted images of crude shapes. He did the same trick with moving images in 1926. An American, Ernst F. W. Alexanderson...