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Conversations with the word “OK” can be heard all over the world. This word is used in the USA at least seven times per day. It has replaced the expression all right or alright, which is still used, although far less frequently than it was hundred years ago. The most significant research into the history of "0 Kay" has been done at Columbia University. OK was first seen in print in the Boston Morning Post of March 23, 1839. When the editor, Charles Gordon Greene was interviewed, he said it stood for all correct, spelled all korrect.
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