Fundamentally it provides the resident with services in the room/suite that he or she is occupying. The services include, but are not limited to:
Bringing ordered meals to the room.
Cleaning and tidying the room.
Changing and replacing sheets and towels.
Restocking the mini-bar and bathroom amenities (soap, lotion, etc).
Repairing the TV, burned out lights, etc.
Showing how to use the AC/heat control.
NOTE: Some of the above tasks are performed daily by House Keeping, but the above are done on demand almost any time when the resident calls for them by room service.