Your Logical Fallacy Is

Your Logical Fallacy Is (YLFI) is a website detailing 24 logical fallacies. The page was constructed by Jesse Richardson, an "ad guy", who attempted to make all of the fallacies as simple as possible.

Ad hominem entry
YLFI:

The entry on ad hominem on YLFI fails to adequately explain what does not count as an ad hominem. Ad hominem isn't just being abusive or mean, it is saying that the person is wrong because of the purported negative characteristic that you attribute to them.

Creationists, for instance, aren't wrong because they are idiots. They are wrong because the evidence doesn't support their point of view. The fact that they persist in believing their point of view in spite of the evidence may be good cause for saying that they are idiots, though. That isn't ad hominem.

Saying "this guy is a wifebeater!" isn't an ad hominem (no, not even if he’s not actually a wifebeater). Saying "you shouldn't believe what this man says about quantum physics because he is a wifebeater" is. See Argumentum ad hominem.