Hey, Gloria ...
Just a little history on those abbreviations. Back in the day when there were no "dot coms", no racing opossums in sig lines, etc. communication by modem was extremely slow.
Users quickly developed abrevs (it would be a sacrilige to call them abbreviations, wouldn't it?) to use in live chat. (Live chat was about as "alive" as road kill, given the fact that a 600 bps modem was a screamer. Those of us who had 1200s were the Richard Pettys of online connection.
Anyway, the abbrevs took hold and some are still around today, proving that there MAY be some good ideas out there. The smiley face also appeared around that time because it was important to get a message across in a two-dimensional world.
IMO = My Opinion
IMHO=In My HUMBLE Opinion
IMNSHO=In My NOT so Humble Opinion
<--AFK means the participant is away from the keyboard
ROFL=Rolling On The Floor Laughing
ROFLMAO=adds "My a@@ off"
ROFLMAOWP= adds "wetting pants"
I'm sure you will find lots more in Kathy's link
Then there is the ubiquitous
(Laughing Out Loud) that some people seem to think is a punctuation mark.
There are also the "bracketies" such as <G> for Grin, <VBG> for Very Big Grin. I would no longer have privileges here if I told you what <VBSEG> means. You will have to look that one up !!! Or ask in e-mail !!!
One of the books I had the most fun writing was "Hitchhikers Guide to the Electronic Highway" when I took this subject up in exhaustive length <VBSEG>.
Have an AbFab time on your cruise. Wish you could tuck me in your suitcase, I could use a warmup before Hawai'i.