In an IHT, some time ago, I found the explanation for the origin of “OK”.
It all started with was is called a “misspelling-based abbreviation”. In the Boston Morning Post of 23 March 1839 it started as a joke: “o.k. – all correct”. Those misspellings were a fad, some did not catch on, like “o.w.” for “oll wright”. But OK survived as we all know.
Now you know, OK?