What do the emoticon symbols even mean on these boards?

I mean, there is one for "disagree", but there is not one for "agree"?

Hello?

And what does the sad face mean? Does it mean you think the comment is sad? Or that the comment makes you sad? Or that you are sad today for reasons that have nothing to do with the post?

The emoticons are silly. They should just make it "agree" or "disagree".