What's the diference between an agnostic and skeptic?

[Beet]

In my experience, "skeptic" is a word people use to describe themselves when they want to make themselves look superior. The opposite of "denier":

"Gee, I'm a 'skeptic' in global warming. I mean, I totally agree that the evidence supports it, it is caused by people, and we need to do major things to stop it, but I'm still skeptical." - said no one ever.