Groups & Roles
Groups & Roles is utility that allows you to create Groups (or Roles) of users. This functionality works mainly to set-up system access rights. Using groups, you assign access rights to users in that group. Once you assign right to the (Access) Group, all users in that group will receive the same rights immediately. That is different from Roles. Access rights of users in Role(s) is not given to the users until they are assigned the Role on each individual Project, Folder or Activity. Assigning User to Role means they are allowed to occupy that particular Role.
Video Tutorial on Roles