A frequent-flyer program (FFP) is a loyalty program offered by many airlines. Typically, airline customers enrolled in the program accumulate frequent-flyer miles (kilometers, points, segments) corresponding to the distance flown on that airline or its partners. There are other ways to accumulate miles: In recent years, more miles were awarded for using co-branded credit and debit cards than for air travel. Acquired miles can be redeemed for air travel, other goods or services, or for increased benefits, such as travel class upgrades, airport lounge access, or priority bookings.
Frequent-flyer programs can be seen as a certain type of virtual currency, one with unidirectional flow of money to purchase miles, but no exchange back into money.
