An online booking system is one of the most effective ways to book an airplane ticket online, says Microsoft, the software giant that makes the system.
In fact, the company says its technology has been used to book more than 3 million flights on its own online system.
The company has partnered with Booking.com to offer its booking app.
The app connects to a server that can automatically find nearby seats for a given flight and automatically book those seats online.
Booking is just one of many services that can help travelers book an airfare.
You can book hotels, restaurants and travel packages.
And the apps also allow people to book tickets to the World Cup, the Oscars and other sporting events.