Acronym        Meaning
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lol            laughing out loud
roflol         rolling on the floor laughing out loud
roflmao        rolling on the floor laughing my ass off
loltime        laughing out loud tears in my eyes
btw            by the way
np             no problem
imo            in my opinion
imho           in my humble opinion
otoh           on the other hand
bbs            be back soon
ib             i'm back
brb            be right back
hb             hurry back
bbl            be back later
ttyl           talk to you later
ttfn           ta-ta for now
afk            away from keyboard
g or <g>       grin
wb             welcome back
wth            what the heck
irl            in real life
k              ok
oic            oh I see
asl            age, sex, location
lo             hello
cya            see ya