the total revenue of airports. Aeronautical revenue Aeronautical revenue are generated through airline rents and landing, passenger service, parking, and hangar fees. Landing fees are charged per aircraft for landing an airplane in the airport property. Landing fees are calculated through the landing weight and the size of the aircraft which varies but most of the airports have a fixed rate and a charge extra for extra weight. Passenger service fees are charges per passengers for the facilities used on a flight like water, food, wifi and shows which is paid while paying for an airline ticket. Aircraft parking is also a major revenue source for airports. Aircraft are parked for a certain amount of time before or after takeoff and have to pay to park there. Every airport has its own rates of parking, for example, John F Kennedy airport in New York City charges $45 per hour for a plane of 100,000 pounds and the price increases with weight. Non-aeronautical revenue Non-aeronautical revenue is gained through things other than aircraft operations. It includes lease revenue from compatible land-use development, non-aeronautical building leases, retail and concession sales, rental car operations, parking and in-airport advertising. Concession revenue is one big part of non-aeronautical revenue airports makes through duty free, bookstores, restaurants and money exchange. Car parking is a growing source of revenue for airports, as more people use the parking facilities of the airport. O'Hare International Airport in Chicago charges $2 per hour for every car. Landside and airside areas Airports are divided into landside and airside zones. The landside is subject to fewer special laws and is part of the public realm, while access to the airside zone is tightly controlled. Landside facilities may include publicly accessible airport check-in desks, shops and ground transportation facilities. The airside area includes all parts of the airport around the aircraft, and the parts of the buildings that are restricted to staff, and sections of these extended to travelling, airside shopping, dining, or waiting passengers. Depending on the airport, passengers and staff must be checked by security or border control before being permitted to enter the airside zone. Conversely, passengers arriving from an international flight must pass through border control and customs to access the landside area, in which they exit, unless in airside transit. Most multi-terminal airports have (variously termed) flight/passenger/air connections buses, moving walkways and/or people movers for inter-terminal airside transit.