The country's flag carrier, Singapore Airlines (SQ) was founded in 1947. It operates from a hub at Singapore Changi Airport (SIN). Singapore Airlines flies to about 65 destinations in 35 countries. It is one of just several airlines that fly to all six inhabited continents. A member of the Star Alliance, Singapore Airlines also has codeshare agreements with 10 airlines that are not part of its alliance. The carrier has five classes of service: Singapore Airlines Suites, First Class, Business Class, Premium Economy Class and Economy Class. However, not every plane in the airline's fleet of 108 aircraft includes each class of service. Singapore Airlines owns several subsidiaries, including Scoot Airlines (TZ), SilkAir (MI) and Tigerair (TR).