Ok, you're new to IGames, and everyone seems to be talking in a foreign language...this short glossary should get you started.

boot = when either IGames kicks you out of a game or your ISP cuts you off.
brb = be right back, bathroom break and other, far more colorful meanings.
gga = good game, all.
gjp = good job, pard.
(g)nma = (good)nice meld, all.
(g)nmp = (good)nice meld, pard.
(g)nha = (good)nice hand, all.
(g)ntu2 = (good)nice try, you two.
gpg = go, pard, go - mentioned here as some use it, but generally regarded as being in poor taste.
lmao = laughing my butt off.
lol = laughing out loud.
OMG = Oh My God! - you'll need this if you're in a game with Babydoll.
rotf = rolling on the floor. Sometimes combined with "lmao".
tram = the rest are mine.
ty(vm) = thank you (very much).
wtgp = way to go, pard.
yw = you're welcome.