I did document control for 20 years. Recently gave it up to emigrate and be a dog groomer.
Document control is pretty much what is says on the tin. You control documents in and out of a company, usually in construction.
Back in the day, documents and their revisions were logged manually on spreadsheets. As time went on electronic document management systems were created where users upload their documents and they all sit for everyone else to access once approved.
Its niche admin, although some people can get funny about being lumped in with admin. We are not administrators, it's much more involved and takes a lot more attention to detail. It sounds easy but not anyone can just be a good DC.