From Encyclopedia Dramatica
j/k stands for "just kiking" and should be accompanied by a picture or emote of a greedy big-nosed jew rubbing his hands together. Most effectively applied after tricking those who are foolish enough to trust you out of shekels, land, or sex.
Benjamin Netanyahu: Lol yeah me too!
Benjamin Netanyahu: j/k lol they're important to our economy.
Ariel Sharon: Bulldoze their homes.
J/K As a Drama-Generating Technique
- Say something really offensive and end it with a "j/k", thereby placing any potential blame squarely upon the jews, WHERE IT BELONGS
OP: chill out goy, I said j/k!
- just kaying
- jay kay (can be confusing, see below)
- just kidding