'OK,' one of the most recognized words on Earth, started as a 19th-century joke abbreviation.

In the 1830s, Boston newspapers went through a fad of playful abbreviations built from intentionally misspelled phrases, things like “KY” for “know yuse” (no use) or “OW” for “oll wright” (all right). The Boston Morning Post first published “OK” in 1839 as shorthand for “oll korrect,” a comic misspelling of “all correct.”

Most of these joke abbreviations faded quickly, but “OK” survived largely by accident: it got a boost from Martin Van Buren’s 1840 presidential campaign, which used “OK” as a nickname referencing his hometown of Old Kinderhook, New York. The combination of the newspaper fad and the political slogan cemented it in everyday use. Today linguists consider “OK” one of the most widely recognized and spoken words in the world, understood across languages that share almost no other English vocabulary.