An airport is a facility that allows planes to land and takes off. Most airports worldwide consist solely of a long, level strip of ground known as a runway. Numerous airports have buildings dedicated to the storage of airplanes and passengers. A terminal is a structure that houses passengers waiting for their planes or luggage. Additionally, airports have structures called hangars that are used to store planes when they are not in use. Certain airports have control structures, such as a control tower that directs planes.