The namespaces that can be associated with the organization namespace (_orgunit, orgunit, or org) are: user, host, service, fs, and site.
For example:
orgunit/doc.com/site/videoconf.bldg-5 names a conference room videoconf located in Building 5 of the site associated with the organization doc.com. (You can also use the alias org for orgunit to form, org/doc.com/site/videoconf.bldg-5.)
orgunit/doc.com/user/mjones names a user mjones in the organization doc.com.
orgunit/doc.com/host/smptserver1 names a machine smptserver1 belonging to the organization doc.com.
orgunit/doc.com/fs/staff/agenda9604/ names a file staff/agenda9604 belonging to the organization doc.com.
orgunit/doc.com/service/calendar names the calendar service for the organization doc.com. This might manage the meeting schedules for the organization.