It is customary to classify the several components of an airport in three major catego- ries: airside facilities; landside facilities; and the terminal building, which serves as the interchange between the two' (see fig.
The airlines industry is structured into three main components: commercial, general, and military. Commercial aviation includes national carriers such as Delta and American, and regional carriers like GoJet and SkyWest Airlines.
This is Seattle-Tacoma's second year in a row winning the award. Seattle-Tacoma also earned a position in the Top 20 Best Airports in the World and landed second place for Cleanest Airport in North America, right behind Vancouver International Airport.
The letters, differentiate between left (L), right (R), or center (C) parallel runways, as applicable: For two parallel runways “L” “R.”For three parallel runways “L” “C” “R.”