Originally established through a partnership of major airlines, and subsequently owned by various entities, Orbitz.com the flagship brand of Orbitz Worldwide has been in operation since 2001. Other Orbitz Worldwide online travel companies include CheapTickets in the Americas; ebookers in Europe; and HotelClub and RatestoGo, based in Sydney. Orbitz Worldwide also owns and operates Orbitz for Business, a corporate travel company. Orbitz was the airline industrys response to the rise of online travel agencies such as Expedia and Travelocity, as well as a solution to lower airline distribution costs. Continental Airlines, Delta Air Lines, Northwest Airlines, and United Airlines, subsequently joined by American Airlines, invested a combined $145 million to start the project in November 1999. It was code-named T2 some claimed, meaning \"Travelocity Terminator\" but adopted the brand name Orbitz when it commenced corporate operations as DUNC, LLC (the initials of its first four founding airlines) in February 2000. The company began Beta testing early the next year, and Orbitz.com officially launched in June 2001.