Air charter is the business of renting whole aircraft (i.e., chartering) instead of buying tickets and reserving single seat. Air charter is regulated by law. While airlines sell places in seats, air charter companies focus on private wealthy customers, urgent cargo, air ambulance services and others. These air charter companies have a lot of different types of aircraft, such as helicopters and business jets. Charter jet categories include turbo props, light jets, mid-size jets, super mid-size jets, heavy jets, and airliners.