It was a short way of writing a different spelling of the words all correct. Some foreign-born people wrote all correct as o-l-l k-o-r-r-e-c-t, and used the letters O.K.
VOA : special.2010.02.28
2
You talk to these people who were standing in front of the bank; the first question you'd ask them, aren't deposits insured in the U.K.
你去银行门前,与排队的人们交谈,先问他们,英国的存款
金融市场课程节选 : 耶鲁公开课
3
They elected Margaret Thatcher and there was a resolve to do something about it but it wasn't just the U.K.; it was all over the world.
他们选举玛格丽特？撒切尔作为主席,并且出台了解决问题的方案,但是不仅仅是英国；全世界都在这样做。
金融市场课程节选 : 耶鲁公开课
4
"But there were a couple "trouble songs" that just weren't working. They were o.k., but I wanted something different.
VOA : standard.2009.04.21
5
O.K. But don't you be thinking that I'm goingto be calling you "sir."