So basically I'm writing two books right now, and there's something that's been bugging me since day one, when I wrote the very first word of the very first chapter of the very first book, and that is, should I really be using "ok" in professional writing, like a book or novel? Or should I be using OK? Which one is correct to use in a professional setting, and if it is one of the two, than what exactly is "Okay" for? This honestly always confused me.
"OK" is definitely not used in professional writing, with the obvious exception being for character dialogue in fiction when it might make sense in the moment. Usually, though, it comes across like a texting phrase, similar to LOL or ROFL, which is a tone that you don't generally want in a novel.
"OK," she said, and put the phone down. "She'll be here at six."
In all other cases besides character dialogue, however, it's one of those casual, slangy abbreviations that comes across poorly. "Okay" works better, even in dialogue.
"Okay," she said, and the put the phone down. "She'll be here at six."
OK and Okay are always in speech. Personally I'm 100% OK with OK. Every reader can read it. (I also use Lunch not Luncheon.)
In minutes of meetings, where a report is summarised then OK is fine. 'Fred reported the Wafflers were OK with the Boxjangles' is a concise and accurate report.
If there was a genuine use in a technical report for alright/OK then always 'alright'. However it is a bit of a red-flag word. 'alright' to me is somebody's casual opinion. Satisfactory, within-limits, as to be expected are a more specific.
"Ok" or any variant feels like a common everyday speech, and thus, it's not adapted to writing/reading, especially for professional quality work.
It could of course be used in dialogue as explained above, but it would still look very ordinary and fill the sentences of words that don't serve a big purpose.
You could illustrate the agreement of one character by describing his/her nod of the head or else, that would be more elaborate.
In one sense, it can enrich your text by bringing different moves, actions, ways of behaving than just confirming with abbreviations like this one.