- 1920 – In the United States, KDKA of Pittsburgh, Pennsylvania starts broadcasting as the first commercial radio station. The first broadcast is the result of the U.S. presidential election, 1920.
- 1936 – The British Broadcasting Corporation initiates the BBC Television Service, the world’s first regular, “high-definition” (then defined as at least 200 lines) service. Renamed BBC1 in 1964, the channel still runs to this day.
- 1947 – In California, designer Howard Hughes performs the maiden (and only) flight of the Spruce Goose or H-4 The Hercules; the largest fixed-wing aircraft ever built.