If you've spent any time on the internet (welcome!), then you have probably come across leetspeak and internet slang. But what is online lingo in one culture might be different in another.
None of this matters if you are still learning the standard language.
This South Korean text book is not just teaching words like "zebra", "zero" or "yak". It is teaching much more.
OMG: Oh My God
W2F: Way to Fail
STFU: Shut the Fuck Up
URANOOB: You're a Noob
LMAOROTF: Laughing My Ass Off, Rolling on The Floor
There's also a :p — or a smiley face sticking its tongue out. Good to see these South Korean students are subliminally learning important things like "STFU".
Korean ESL Textbook - OMG! [Engrish Brog]