Beginning in the third decade of the twentieth century, talking pictures, radio, and then television appeared on the American scene. Along with recorded music available first on phonograph records and then on such devices as compact discs, these three forms of entertainment, each of which relied on the mechanical transmission of sound into homes or movie theaters, dominated American popular culture between 1928 and the end of the century.
Each year, Americans sampled the available movies, radio programs, and television programs. Their choices reflected the categories that divided them, such as gender, region, race, and ethnicity, but the fact that all chose from the same basic menu meant that popular culture united Americans far more than it separated them. Even regional forms of entertainment, such as the country music broadcast over the Grand Ole Opry program from Nashville, reached wide audiences.