O.K., OK, Ok, ok, okay?

Which one is proper usage? Which one do you use?

I usually go for O.K. or okay.

Okie Dokie! Or OK. Sometimes I will write out okay.

In the 20s some people spelled it okeh.

Depending on what feeling I want to convey, OK or okay. I realize they’re said the same but OK seems like it’s said shorter.

*“OK” and “okay” are proper. I use “OK” normally, but I would use “okay” as a verb.
*Merriam-Webster

Usually “ok” is what I use.
Until I wondered if it was really a word I used to use “okay.”

“O.K.” looks like yelling in the evenly sized text of the computer screen.

OK.

But I only use it informally. I would never use it in a document or an official email, but perhaps in response to someone.

“OK. I’ll see you at 1:00” and the like.

I never type the periods, it’s always “Ok” or “Okay” or “Okey.” How about simply “k”?

M’kay.

And, of course, umkay is OK.

Fuck yeah!

But when that’s not appropriate, I go with “okay.”

A’ight.

Nope, the label Okeh was taken from the initials of the man who started it.

10-4

Okily-dokily

What the heck does O.K. stand for? If anything.

We don’t really know.
There are a few competing ideas.
Some say it was from ‘Orl Korrect’, as in ‘All Correct’ as written by Andrew Jackson, one of the early US presidents.
Some say it came from the O. K. Club.

Ah… here we go: What does “OK” stand for? - The Straight Dope

[The Master speaks](Dear Ms. Stinson,).