The Community Activities Hub is a place for communities to come together. A community, in this space is defined as a group of people who share an activity. Here, sharing an activity does not imply (only) that everyone in the group performs the same activity, different parts or tasks constituting an activity could also be performed by different people. Indeed an activity typically consists of more that one tasks, which translate to "operations" on an application where an operation is a single UI action such as submitting a form, or doing a search.
Communities are different from collectives, which differ from cooperatives in the degree to which their processess and structures are defined. Thus communities can start as a loose group of users/members. As roles and activities are evolve over time, structures/processes get clearly defined till they may be formalized as cooperatives.
The community activity hub enables this transition at each step, and builds on Elinor Ostrom's notions of the "commons", adapting it to the digital realm.