Airline reservation systems (ARS) are systems that allow an airline to sell their inventory (seats). It contains information on schedules and fares and contains a database of reservations (or passenger name records) and of tickets issued (if applicable).

An Airline Reservation System (ARS) in 2026 is a multi-layered digital infrastructure that handles inventory, pricing, and ticketing. At its core is the Passenger Service System (PSS), which contains modules for inventory (tracking every seat in real-time) and the Departure Control System (DCS). When you search for a flight, the system communicates via a Global Distribution System (GDS)—like Amadeus or Sabre—which acts as a bridge between the airline's database and travel agents or websites. The system uses dynamic pricing algorithms to adjust fares based on demand and remaining seats. Once you book, it generates a Passenger Name Record (PNR), a unique 6-character alphanumeric code that stores your data. This PNR is the "digital thread" that connects your payment, seat selection, and baggage information across all airport systems until you reach your destination.