The word O.K. was firstly used in 1838 by Boston newspaper. They tried to come up with the way to make the journal more interesting by using acronyms such as I.D.N (I don't know).
The acronym was getting distorted from time to time and one of them is O.W. which stands for All right because the pronunciation is similar to Oll Wright as well as O.K. which stands for All Correct because the pronunciation is similar to Oll Korrect.
However, the O.K. would have been forgotten over time had it not been used in the campaign for U.S. President of Martin Van Buren.
The O.K. Club was established to support Van Buren in the election. This O.K. stands for Old Kinderhook which is his hometown. Even though he lost the election it brought a big popularity to the word O.K.
The popularity of O.K. is widesperad and continue until present.