The WorkGroup is a set of tools provided to professionals in order to accomplish their tasks organised and easily. Some collaborative tools provided are file sharing, direct communiction and contract binding (printable and digital) grouped in Stages for better monitoring. These stages appear in the right side of the screen after you select to view a WorkGroup. You may find more details for every Stage in the corresponding questions.
Note that the WorkGroup appears only to its members and neither to the rest of the users of the platform, nor publicly on the Internet.