I am too new to decipher anything about them. Please add a summary or remove these tags.
closing was just a terrible tag to begin with. I've retagged all the questions that had it, a lot of which went all over the place, a couple of which were not related to the closing process at all. I imagine the close tag will be just as bad.
I believe that close should be synonymized with vote-to-close as the majority of questions go there, but please manually retag all the questions there first to make sure they all end up in the right place in the end. The first tag was a mess so it's safe to assume this one will be as well (and I'm tired and don't feel like going through that one at the moment).