any atompub server exposes a "service document" (http://tools.ietf.org/html/rfc5023#section-8) that describes what the server is exposing. each service document lists a set of "workspaces" (http://tools.ietf.org/html/rfc5023#section-8.1), which are just a grouping construct for "collections". workspaces have no interaction semantics in atompub, there is no protocol for creating or deleting them; they just exist. each workspace lists a set of "collections" (http://tools.ietf.org/html/rfc5023#section-10), which is by far the most central construct in atompub. a collection can be listed in more than one workspace. [Model Aspect] 
service basics