GDS

Global Distribution System

A worldwide computerized reservation network used as a single point of access for reserving airline seats, hotel rooms, rental cars, and other travel related items by travel agents, online reservation sites, and large corporations.
The premier global distribution systems are
Amadeus
Abacus
Galileo
Sabre
They are owned and operated as joint ventures by major airlines, car rental companies, and hotel groups.
Also called automated reservation system (ARS) or computerized reservation system (CRS)