Project rooms are the main component of CommSy. They allow their members to work collaboratively, exchange materials, join discussions, and so on. Users first log in to CommSy—the “house”—and then enter a project room through its virtual “door.” Depending on the setting chosen by the room moderator, users can enter a room (a) immediately by clicking its door, (b) by entering the membership code set by the moderator, or (c) after the room moderator manually approves their membership request. In case of option (c), prospective members are asked to write a short text in which they explain to the room moderator why they wish to join the project room. Anyone with an UHH user account can create a new project room. To do this, log in to CommSy and click “Create new room” on the dashboard.