See the documentation Here basically it is specifynig where you are going to upload your artifact to, e.g. a local maven repository (Nexus, Artifactory etc) or perhaps a hosted repository out there on the internet (e.g. Central)
You'll need to talk to the people who run the Jboss repository, it'll be limited as to who can upload what. In general you won't need to upload artifacts to an external repo like this unless you are at the stage where your code is ready to share with hte world. For a more localised sharing you'll want to install something like Nexus or Artifactory, you then upload your artifacts to them and that can be shared across your local network etc.