right so something changed what was it what is a group
I think it's the stuff that you are in. Like if you out your name in the OMTL, you are officially in that group. Or you put your name in the "Expo Friend's Tag List" you are in that group.
A group is a group of people. So let's say you want everyone to see something. Instead if copying and pasting it, you can just type
@omtl and be done with it. Everyone would be tagged. You can also tag other groups.