Common abbreviations online forum users use:
LOL - Laugh out loud
PMSL - Pissing myself laughing
ROFL - Rolling on floor laughing
LMAO - Laughing my arse off
DH - Dear husband
DW - Dear wife
OH - Other half
DP - Dear partner
DF - Dear fiance/fiancee
DS - Dear son
DD - Dear daughter
DSS - Dear stepson
DSD - Dear stepdaughter
MIL - Mother in law
FIL - Father in law
SIL - Sister in law
BIL - Brother in law
IMO - In my opinion
IMHO - In my humble opinion
BRB - Be right back
IYKWIM - If you know what I mean
IYSWIM - If you see what I mean
IDK - I don't know
SAHM/D/P - Stay at home Mum/Dad/Parent
BF - Boyfriend OR Breastfeeding
GF - Girlfriend
SO - Significant other
TIA - Thanks in advance
TTC - Trying to conceive
EDD - Estimated due date
FAQ - Frequently asked questions
DOB - Date of birth
AF - Aunt flow (Period)
MIA - Missing in action
AWOL - Absent without leave
24/7 - 24 hours a day, 7 days a week
BTW - By the way
G2G - Got to go
FYI - For your information
GL - Good luck
HTH - Hope that helps
JMO - Just my opinion
MOF - Matter of fact
MYOB - Mind your own business
A TROLL is a prat who deliberately posts thing to cause offence and create drama. DO NOT FEED THE TROLLS!
Feel free to add more