No0bs Guide To Internet Slang

[CHAINS]

Here's J and K:

J

Jaggy - Aliased computer graphics
JK or j/k - Just kidding, or joke
JFGI - Just ~censored~/Freaking Google It

K

k or kk - OK
KISS - Keep it simple stupid.
KS(ing) - Kill-Steal(ing)
KOS - Kill on sight
KTHX - OK, thanks
KTHXBAI or KTHXBYE - OK, thanks, goodbye, used either to cut short a conversation or to express displeasure with being cut short