The document provides a history of radio broadcasting from 1900-1950. It describes key early innovations including Reginald Fessenden making the first radio broadcast in 1905 of music and a Bible reading. Commercial radio began in the 1920s with stations like KDKA broadcasting election results. The rise of networks like NBC and CBS in the 1930s led to regulation by the Federal Communications Commission to reduce interference. During World War II, radio became an important source of news and entertainment and helped the industry grow further in the postwar years, until the rise of television in the late 1940s began to compete for audiences and sponsors.