Businesses listed under Flights provide air transport for passengers between airports, usually on scheduled domestic or international services. Airlines operate aircraft and manage routes, timetables, check-in, boarding and in-flight arrangements. Some services are seasonal, chartered or tailored to particular destinations, while others form part of a wider network with connecting journeys. Customers may be able to search for routes, compare available departures and book tickets directly with an airline or through a flight-booking agent. Related services can include seat selection, baggage allowances, travel changes, cancellations and assistance with special requirements; the options depend on the provider and ticket conditions. Flight operators and booking businesses are distinct: an agent arranges reservations, while the airline or charter operator is responsible for carrying passengers.