I've been copying "sample" `settings.xml` files for ages now, and almost all of them seem to include a repository with the URL `http://central`. This bugs me, because of course there could actually be a machine on the local domain called "central", so this is a valid URN, but it also must (might?) have some special meaning to Maven.

Is it just shorthand that's commonly used, but the actual URL is ignored? Could I replace it with something else, or remove it entirely? Is it documented anywhere?

If it matters, I develop on a corporate network that has an internal iBiblio mirror, that acts as "central" for us.