Almost everyone in the United States watches television. About 99 percent of homes have at least one television set, and, on average, the set stays on for slightly more than seven hours each day. Most viewers have favorite television programs, and they may even have favorite channels. What most viewers may not think about is how the channels and programs get to the set.

Television broadcasting is still the most prevalent form of television in the United States—compared to cable television, for example, which reaches around 70 percent of U.S. homes. Broadcasters also transmit the television programs that reach the largest audiences. Even though their share of the television audience has been decreasing since the 1980s, broadcasters still stand at the center of the television industry.

The Television Broadcasting System

About fifteen hundred television stations make up the core of the television broadcasting system. Each is...