Specialized or En-situ service
It is basically a banquet, which is pre determined or may have a special menu. The food stuffs are brought to the customers and the clearance is done either by the staff or guest.
Tray: Whole or a part of the meal is brought on the tray, to the guest. Basically, common in Outdoor Caterings and banquet parties.
Trolley: If the guest is busy in some other work and he/she is not available at the dining hall, then the food is collected on a trolley is carried to the guest.
Home Delivery: Various restaurants or fast foods and take away provides this useful facility to their customers. This home delivery can be free or sometimes charges are also levied.