OK and Okay

OK came before Okay, but we just don't know for certain who started to use OK first or what it meant.

The best two theories that I know of are the following.

OK is an abbreviation for the words all correct in the Dutch language. If you ever get a copy of the March 23, 1839 Boston Morning Post, you will find the earliest known mass media use of the term.

OK is an abbreviation for Old Kinderhook. Martin Van Buren went by the nickname Old Kinderhook. Apparently, he used to sign off on things with the initials OK. When he ran for president in 1840, there was actually an OK Club formed to support him.

This topic leads to fierce debate because no one really knows the origin. There are plenty of alternative explanations if you don't like the ones that I presented. All we can say for sure is that the abbreviation OK came before the word Okay. Now, ain't that weird?