Workspace is a virtual group which will contain team members. You can add new members to the group and you can delete members. Each member in your Workspace will have a security level (Manager, Participant, Guest). By default the person who created the group will be Manager. He can invite other members into one of the 3 roles.
A workspace will be useful only when it contains one or more Tools. Tools can be created both by Manager and Participant. But only Manager can delete tools.