AFAIK means “As far as I know”
AMA means “Ask me anything”, a Q&A style discussion with the author of a post.
CCW means “Comments and criticism welcome”
CMV means “Change my view”
DAE means “Does anybody else or does anyone else”
DM;HS means “Doesn’t matter; had sex”
ELI5 means "Explain like I'm 5 (years old)"
FIFY and FTFY mean “Fixed It For You” and "Fixed that for you", respectively.
FWP means “First world problems”
GGG is a reference to the “Good Guy Greg” or “Good Girl Gina” meme
GTFO means “Get the f**k out”
HIFW means “How I feel when”
HMB means “Hold my beer”
IAmA means "I am a.” This is the standard way to begin the title of an AMA (Ask me anything) post.
IANAD means "I am not a doctor"
IANAL means "I am not a lawyer"
IIRC means "If I recall correctly"
IMO and IMHO mean "In my opinion" and "In my humble/honest opinion", respectively.
IRL means “In real life”
ITT means "In this thread"
LOL means “Laugh out loud”
LoL means “League of Legends”, a popular online game.
MRW and MFW mean "My reaction when" and "My face when", respectively.
NSFL means "Not safe for life" (explicit and offensive; often gore)
NSFW means "Not safe for work" (This label means that content may be considered offensive, and inappropriate for viewing in public spaces or when minors are present.This label covers, but is not limited to, any mature or explicit content, and can also include bawdy references or stories.)
OAG references the “Overly attached girlfriend” meme
OC means “Original content”, meaning the author of the post created the content shown or linked in the post.
OP means "Original poster", the author of the post.
PSA means "Public service announcement"
SMH means “shake/shaking my head”
SO means “Significant other”
TIFU means “Today I f**ked up”
TIL means "Today I learned"
TL;DR means "Too long; Didn't read.” Sometimes used as a synonym for summary.
WIP means “Work in progress"
YMMV means “Your mileage may vary”
YSK means "You should know"
ಠ_ಠ is an emoticon that means disapproval. Often used sarcastically.
Congratulations to our winners of the Mini Game.