Drawing is a form of visual art that makes use of any number of drawing instruments to mark a two-dimensional medium. Instruments used include graphite pencils, pen and ink, inked brushes, wax color pencils, crayons, charcoal, chalk, pastels, various kinds of erasers, markers, styluses, and various metals. An artist who practices or works in drawing may be called a draftsman or draughtsman. A small amount of material is released onto the two dimensional medium, leaving a visible mark.