Although the Radio was a major innovation of the 1920's, it's major impact was during the last years of the 20's and the early years of the 1930's when Americans suffered in the throes of the Great Depression.
The primary impact of the radio is that it provided a valuable diversion for Americans who did not need to leave home in search of entertainment. Whereas previously Americans spent their leisure hours reading, viewing a stereoptican (a 3-D device) or singing at the piano, the radio offered entertainment which the entire family could enjoy together Whole families gathered near the radio to listen to programs such as Young Widder Brown, Gun Smoke, The Lone Ranger, Mystery Theater, or even The Green Hornet. Unlike movies, the radio provided free entertainment which made it immensely popular. In addition to entertainment, the radio provided a convenient source for news and political addresses. During the early years of his administration, President Franklin Roosevelt managed to sooth the anxieties of many Americans suffering from the Great Depression with his radio "fireside chats." Previously, Americans had to rely on newspapers to keep up with current events.
Of course, with the advent of the radio came the commercial. Radio listeners were exposed to advertisements for products from cigarettes to dog food.. Many had musical ditties, such as the following for Pepsodent Toothpaste:
You'll wonder where the yellow went
When you brush your teeth with Pepsodent.
Annoying as they may now seem, radio commercials provided a tremendous boost to the American economy, as consumers were exposed to information about products for sale. The end result was a tremendous increase in retail sales, and the birth of an entirely new industry: advertising. None of this would have happened had it not been for the creation and dissemination of the radio.
The impact of the radio not only in the roaring twenties, but all of human life afterwards cannot be over exaggerated. The radio impacted the twenties in three key ways.
First, the radio in twenties created a new form of entertainment. It was a huge step forward in this area. This created a culture that prized entertainment, which America still espouses today.
Second, the radio began to democratize knowledge, information, the news, and so much more. To be sure, not all could afford the radio in the 1920s, but in time a radio would be in the home of every American and the airwaves could bring all sorts of things in an instant.
Third, the radio also helped to make the nation smaller as it helped to create a popular culture. This began in the 1920s and continued.