It's a reputation system that is used when people want to pay you a compliment about your post or just in general.
I don't know all the details but to rep someone, you just click on the yellow "smiley face thingy" & then write in your comment(s). Then the person you rep gets rep points based on certain criteria--which I haven't figured out yet(as far as why some rep points count as more than others)!
LOL They started the rep system when all of the changes were made around here recently. I hope that I answered your question okay.
If you have any more questions, I'd be more than happy to try & answer them for you!
:rose: