1 min
Where did the word "OK" actually come from?
"OK" probably began as a deliberate spelling joke. In 1839, Boston newspaper editors misspelled "all correct" as "oll korrect" and shortened it to O.K. — purely for fun.

Answer
The answer is a bit ridiculous: "OK" most likely began as a spelling mistake used as a joke.
In 1839, newspaper editors in Boston had a fashion for abbreviations — deliberately misspelled ones, used as running gags. "All correct" was misspelled on purpose as "oll korrect", then shortened to O.K. On 23 March 1839, the Boston Morning Post printed it. It was nothing more than a word game.
What turned O.K. into a national word was the 1840 American election. The candidate Martin Van Buren had the nickname "Old Kinderhook", after the town where he was born, and his supporters formed the O.K. Club to campaign for him. "OK" went up on walls all over the country and became a hit almost overnight.
The story that it stands for "0 killed" — no casualties — was attached much later. Language historians generally treat that as a story invented afterwards, not the real origin.
In one line: the most widely understood word humans have ever made began as a typo someone thought was funny.
A stranger fact: because OK is only two letters and is hard to misread, it became the standard word for "received and understood" in the telegraph era of the 19th century. That is a big part of how it travelled the world.
Michael's Thought
The most understood word on Earth started as a typo. It makes me think a joke can travel further than something serious.
Sources
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