Although decorative windsocks originated in Japan and China centuries ago, their purpose and design took a new direction with the advent of aviation.
Planes take off into the wind - with the wind blowing into the front of the plane - to give the wings greater lift. Pilots also land into the wind for greater control of the aircraft. Pilots must know the direction of the wind and be able to gage wind speed in order to take off and land safely. In the early days of aviation, a simple flag or streamer may have been the beginning of the practical windsock, a tapered cone open at each end to allow wind to blow through and thus indicate wind direction and velocity.
The larger opening of the sock, the "throat", catches the wind. The taper of the windsock funnels the wind toward the small end of the sock, the "tail", which blows "with the wind" and indicates wind direction. Along with design, visibility is important. Windsocks used in aviation are usually vivid safety orange, a color that provides good contrast to the blue color of the sky. Safety orange is also known as blaze orange and international orange.
High visibility windsocks also have an important industrial application. They are often seen at chemical plants and other types of industrial plants to indicate wind direction in case of an accident in which potentially hazardous chemicals are released.
Through the centuries since their creation, windsocks have been considered a symbol of longevity and good luck. Considering the importance of windsocks from a safety point of view, the symbolism certainly applies in the areas of aviation and industrial manufacturing.