ok

OK, also written okay, is a versatile term used as an interjection, adjective, adverb, or noun to express assent, acceptance, adequacy, or permission. In conversation it signals agreement or that something is acceptable; in writing it often means satisfactory or that one may proceed. Because of its brevity and neutrality, OK has become a common everyday part of global communication.

Most linguists trace OK to the 1830s in the United States, where "oll korrect"—a humorous misspelling of "all correct"—appeared in print. The form gained popularity during the 1840 presidential campaign of Martin Van Buren, whose nickname was Old Kinderhook; supporters formed the OK Club and widely used the term. While other theories (such as a Native American token "okeh") exist, the "oll korrect" origin is the most widely accepted.

OK is now used internationally and is typically written in uppercase as OK, though "Okay" and "okay" are also common, especially in more casual text. In many languages the term is borrowed directly as OK, while some have their own native equivalents. The term also appears in computer interfaces, product branding, and as a standard sign of approval in signage and electronics. A separate but related phenomenon is the OK hand gesture, where the thumb and forefinger form a circle.

Overall, OK serves as a flexible, neutral cue for agreement, permission, or adequacy, supporting concise communication across spoken and written discourse.