A waiting room or waiting hall is a building, or more commonly a part of a building or a room, where people sit or stand until the event or appointment for which they are waiting begins. There are two types of waiting room. One has individuals leave for appointments one at a time or in small groups, for instance at a doctor's office, a hospital triage area, or outside a school headmaster's office. The other has people leave en masse such as those at railway stations, bus stations, and airports. Both examples also highlight the difference between waiting rooms in which one is asked to wait (private waiting rooms) and waiting rooms in which one can enter at will (public waiting rooms). Order in private rooms People in private waiting rooms are queued up based on various methods in different types of waiting rooms. In hospital emergency department waiting areas, patients are triaged by a nurse, and they are seen by the doctor depending on the severity of their medical condition. In a doctor's or dentist's waiting room, patients are generally seen in the order in which their appointments are for, with the exception of emergency cases, which get seen immediately upon their arrival. In Canada, where there is publicly-provided health care, controversy has arisen when some important people or celebrities have jumped the line (which is supposed to be based on the appointment order or by severity of condition). In some government offices, such as motor vehicle registration offices or social assistance services, there is a "first-come, first-served" approach in which clients take a number when they arrive. The clients are then seen in the order of their number. In the 2010s, some government offices have a triage-based variant of the first-come, first-served approach, in which some clients are seen by the civil servants faster than others, depending on the nature of their service request and/or the availability of civil servants. This approach can lead to frustration for clients who are waiting, because one client who has been waiting for 30 minutes may see another client come in, take a number, and then be seen within five minutes. In car repair businesses, clients typically wait until their vehicle is repaired; the service manager can only give an estimate of the approximate waiting time. Clients waiting in the entrance or waiting area of a restaurant for a table normally are