Kansas City standard
A 1975 attempt to store computer programs as audio on ordinary cassette tape using one vendor-neutral encoding.
The backdrop was chaos: every early home computer saved to cassette in its own incompatible way. At a symposium in Kansas City in November 1975, convened around BYTE magazine, a group settled on a format. Bits were encoded as tones via frequency-shift keying (FSK) — a zero as four cycles of 1200 Hz, a one as eight cycles of 2400 Hz — the same basic trick a modem uses.
The rate was 300 baud, i.e. glacial. It caught on with the likes of Ohio Scientific, but the big names (Commodore, TRS-80) went their own faster ways regardless. A monument to the era when your storage medium was a two-dollar cassette from the supermarket.