Here are some slang turned into real words. Excample:

OMG!! = Oh my god!!

Real thing:

goi = get over it
ttyl = talk to you later
u = you
r = are
Wuu2? = what you up to?
Wubu2? = what you been up to?
g2g = got to go
bbl = be back later
wb = welcome back
ty = thank you
btw = by the way
bck = back
y = why
brb = be right back
bb = bye bye

I think I've covered it but if i've missed any then feel free to ask in comment,ty. bb!!!