That's something about signing up and agreeing to be a nice person. I can't recall exactly, but basically agreeing to be polite at all times and maybe even helping to keep the forum a happy place. If you post a message in Talk To The Team, someone there can provide the details.
that sounds like a plausible reason, but actually it's when you do Horse Forum the courtesy of posting a link to our web site, on YOUR web site. then you can post a link to YOUR website in your signature line. but, you have to do through the admin folks, since they are the only ones who can put the heart by your user name.
we are ALL nice, aren't we???? well, . . . aren't we?