It doesn't really matter. Since texting seems to be all about abbreviations the 'k' is probably the most consistent.
You may be interested to know that the Japanese word for OK is "yosh". I was once talking to a Japanese national and used "yoshi doshi". It didn't take him long to work out that meant "okey dokey". My personal contribution to Nihon-go.
And, apropos the picture with your question, you're wrong. There are only 10 kinds of people in the world: those who understand binary and those who don't.
It just feel like the most proper answer for me is okay. I´m okay with k and ok but I feel happier when I hear an okay. And I think k sounds even nicer if u put an extra word after it. But also k is a faster way to type. But I see okay as more caring and I just like it more. But it also depends who I talk to. if it´s someone close to me I like okay more or k followed with another word after.
You may be interested to know that the Japanese word for OK is "yosh". I was once talking to a Japanese national and used "yoshi doshi". It didn't take him long to work out that meant "okey dokey". My personal contribution to Nihon-go.
And, apropos the picture with your question, you're wrong. There are only 10 kinds of people in the world: those who understand binary and those who don't.
That's just about the extent of my ability. :(
It depends who I am texting to, for most people I use K.
Ok is alright but the other one just NO
ok = everything’s cool.
ok? = you make no sense.
ok… = you’re creepy.
okayy = i don’t care.
Ok. = i’m so pissed off.