Between the 1920 launch of the first mass market music radio and the late 1940s, before televisions were mass-marketed, radio was the primary way in which Americans consumed live news and entertainment. For many years, it was the only source of immediate mass communication available to most people. It enabled the same creative programming and music to become available to most Americans, and it united Americans in terror during the infamous 1938 broadcast of Orson Welles' "War of the Worlds" dramatization -- and again in 1945 to greet World War II's end. Radio's live news and entertainment dominance lasted until the widespread introduction of television during the 1950s.

Appealing to the Masses

During the 1950s, as televisions spread to more and more homes throughout America, many assumed that radio's days were numbered. One way in which radio overcame these predictions involved the promotion of entertainment content that would appeal to the masses. For radio, this meant finding and publicizing acts with mass appeal like the Beatles and Elvis Presley. The radio industry also developed catchy jingles to punctuate sports and news coverage, and to let people know what type of programming was upcoming.

Appealing to Youth

The radio industry realized the importance of the youth market in cultural consumption. The expansion and mass popularity of rock-and-roll music among young people was a crucial element of this appeal. The stardom of the era's legendary performers -- from Elvis Presley to the Rolling Stones -- was driven by young people, sometimes over the objections of their parents. Top 40 radio became a weekly staple. Disc jockeys also cultivated their own personalities and followings, some becoming famous in their own right.

Branding and Diversification

During the 1950s, the radio industry balanced the need for mass audiences with increasingly diverse offerings. As news delivery and scripted entertainment came to be dominated by television, more and more specialized radio stations began to form. Diversification began as early as the 1920s, and by the 1950s, radio stations were available that specialized in everything from opera to classical country music. Stations associated with the musical styles of cities and regions -- like Delta blues, Memphis soul and New Orleans jazz -- also sprouted up.

Technological Innovation

Radio has continued to survive in part because of its willingness to adjust to changing tastes, plus its efforts to stay cutting edge. Its survival is also due to its keeping up with technological developments in mass communication. The development of satellite radio and the mass availability of internet radio in contemporary culture has kept radio as immediate and accessible as any other form of media, including television. Meanwhile, partly thanks to the popularity of independent music, diversification reaches greater and greater heights.