Where can I get up-to-date airline, flight, route and price data? [closed]

Question

Where do sites like Expedia, Orbitz, Kayak, Bing Travel, etc. get their airline schedule data? E.g. if I was going to build some sort of site to find air travel, what data sources exist that I can use?

I've found OpenFlights.org so far but this won't get me pricing information and it doesn't have actual flight information (e.g. information for a particual flight number - just the routes) so I can't tell where the layovers, etc. are.

Answer 1

Online shopping/booking engines either get and display the data from internal GDS or they use a direct connect (API) with the distributer or supplier