It is a function addressed to projects that are managed in the group (for instance, by a charity, community, sports team, music band, etc.).
With the Team function, you can invite other people to join your project as a team, so they can share it, post updates, etc. The organizer of the project can check all the activities that other team members did on the project, like sharing and collecting support.
This function is recommendable for projects that need to be managed by more than one person, to be able to achieve a better result.
If you are interested in using the Team function, go to the [My project] page and select the option to run your project as a team.