The popular word can be spelled just about any reasonable way: O.K., OK, ok, okay. The term originated during an 1830s New England slang fad as the abbreviation of the purposeful misspelling oll korrect. While O.K. is the most historically accurate, it is also by far the least used. Only The New Yorker, as usual, still considers O.K. the proper spelling, spurning even its own preferred dictionary. I suggest the most common spelling, okay, which follows standard capitalization, does not stand out unnecessarily in writing, and cannot be confused for any other abbreviation.