Internet slang always in the form of acronyms. Google "acroslang" and you will find other people talking about it.
Acroslang is popular everywhere from txt messages to 4chan.
Examples of very popular acroslang on 4chan would be "mfw" (my face when) and "gtfo" (get the fuck out; usually used with rule 31: "TITS OR 'GTFO'").
Examples of very popular general acroslang would be "lol" (laugh out loud), "wtf" (what the fuck), "stfu" (shut the fuck up), and so forth.