OES services require you to create User objects to represent the users on your system. The Linux User Management (LUM) component on OES also requires you to create a LUM-enabled Group object to which you can assign the users.
In addition to these basic objects, it is usually helpful to organize your tree structure by using Organizational Unit objects to represent the structure of your organization and to serve as container objects to help manage the users, groups, servers, printers, and other organization resources you can manage through eDirectory.
For detailed information on understanding, creating, and managing the various objects your organization might require, see the NetIQ eDirectory Administration Guide.