The first radio broadcast was made by Reginald Fessenden on Christmas Eve, 1906, from Brant Rock, Massachusetts.

Lee De Forest invented the Audion, the first practical radio receiver, in 1906.

KDKA was the first commercial radio station in the United States, broadcasting from Pittsburgh, Pennsylvania, on November 2, 1920.

Warren G. Harding gave the first radio address by a president of the United States on June 14, 1922.

NBC was the first national radio network in the United States, founded in 1926.

Amos 'n' Andy is credited with being the first soap opera, first broadcast in 1928.

W1XOJ was the first FM radio station in the United States, broadcasting from Boston, Massachusetts, in 1936.

Information Please is credited with being the first quiz show, first broadcast in 1938.

The Regency TR-1 was the first transistor radio, introduced in 1954.

The Larry King Show is credited with being the first talk show, first broadcast in 1985.

Sirius was the first satellite radio service in the United States, launched in 2001.

The Adam Carolla Show is credited with being the first podcast, first broadcast in 2005.

RealAudio was the first internet radio service, launched in 1995.

Shoutcast is credited with being the first streaming radio service, launched in 1999.

HD Radio was the first digital radio service in the United States, launched in 2002.