Does OK have periods?

Does OK have periods? According to Gregg Reference Manual, okay is written without periods. “In sentences, the forms okay, okayed, and okaying look better than OK, OK’d, and OK’ing, but the latter forms may be used.” When used as a verb, spelling okay out is preferred. OK is the form supported by Merriam-Webster and the AP style guide.

According to Gregg Reference Manual, okay is written without periods. “In sentences, the forms okay, okayed, and okaying look better than OK, OK’d, and OK’ing, but the latter forms may be used.” When used as a verb, spelling okay out is preferred. OK is the form supported by Merriam-Webster and the AP style guide.