The first time i ever heard of these abbreviations was in an email my best friend sent to me in 4th grade.
LOL = Laugh out Loud
J/K= just kidding
J/P= Just playing
brb= be right back
ttyl= talk to you later
u = you
c = see
r = are
b = be
ur = your/you're
l8r = later
bbl = be back later
btw = by the way
idk = i don't know
fyi = for your information
2morrow = tomorrow
2 = to
QT= cutie
jw = just wondering
gr8 = great
g2g = got to go
email me if you have anymore... if you really think about it, this page is really funny, because this is a language that only makes sense to the teenage generation, and now all generations can understand it!!!