Ok

ok (sic) as a response to a topic was first used by Burnt_Potatoes and later popularized by Lonta_Beans and is used to generally denote a lack of interest or engagement in a topic, particularly topics that are seen as worn out, or very poor trolling attempts. It's use is to show that a thread does not deserve any more effort given to respond to it than typing two letters. Newer board members occasionally interpret decry this practice as trolling but everyone eventually posts ok in response to a thread, sooner or later.