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  In 1946, American Airlines installed the first automated booking system, the experimental electromechanical Reservisor.
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  airline reservation system (ARS) , 1959, was established.
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  Semi-Automatic Business Research Environment (SABRE), launched
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  The Holidex reservation system introduced in 1965. This was the first computerized hotel reservation system
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  Delta Air Lines launched the Delta Automated Travel Account System (DATAS) in 1968.
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  United Airlines and Trans World Airlines followed launched Apollo Reservation System and Programmed Airline Reservation System (PARS)
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  In 1976, United began offering its Apollo system to travel agents;