Either uppercase or lowercase is acceptable.

OK is an informal spoken word. It means: OK, that's acceptable. You can also agree, agree. OK can also be written as ok or o.k, with the same pronunciation. It is also the most famous English word in the world.

There have been many studies on the origin of the word OK, among which alan walker Reid finally confirmed that OK originated from a joke. Someone pronounced the phrase all correct as oll (or orl) correct, this person or others spelled it as oll korrect, and finally abbreviated it as OK.

Example:

I'm going to see if she's okay. ?

I'll see what's wrong with her.

I just stopped by to see if you were okay. ?

I just came by to see if you were okay.

Extended data:

Synonyms for OK:

1, OK:

Ex.: Nothing!

Translation: Good!

Among them, all right spoken English can also be changed to ok, which means good!

2. Fine (OK, everything is fine):

Ex.: I'm fine!

I'm fine!

Baidu encyclopedia -OK