( as a regular reader of Reddit, I need to keep up heh )

AFAIK - As Far As I Know
BTW - By The Way
ELI5 - Explain Like I'm Five (years old)
FTW - For The Win (awesome achievement)
GFY - Go Fuk Yourself
GTFO - Get The Fuk Out (of here)
ICYMI - In Case You Missed It
IDK / IDNKT - I Don't Know / I Did Not Know That
IHML - I Hate My Life (one who still lives with his mama)
IIRC - If I Recall Correctly
IKR - I Know Right! (affirming agreement)
IMHO - (or IMO) In My Humble Opinion
JFYI / FYI - Just For Your Information
LYK - Let You Know
TBH - To Be Honest
TIL - Today I Learned (also a popular subreddit)
YOLO - You Only Live Once (like investing into a meme stock like a fool)