Airbrush painting is achieved with an instrument for spraying paint or varnish by means of compressed air. It looks like a fountain pen and is held in a similar fashion, the pressure of the forefinger on a lever regulating the air supply. It can be controlled so as to give large areas of flat color, delicate gradations, or a fine mist. The airbrush was invented in 1893. In the early 20th century airbrushes were used mainly for photographic retouching, and their principal use is now in commercial art.