Drawing is a form of visual expression and is one of the major forms within the visual arts. There are a number of subcategories of drawing, including cartooning. Certain drawing methods or approaches, such as "doodling" and other informal kinds of drawing such as drawing in the fog a shower leaves on a bathroom mirror, or the surrealist method of "entoptic graphomania", in which dots are made at the sites of impurities in a blank sheet of paper, and lines are then made between the dots, may or may not be considered as part of "drawing" as a "fine art." The word 'drawing' is used as both a verb and a noun: * Drawing (verb) is the act of making marks on a surface so as to create an image, form or shape. * The produced image is also called a drawing (noun). A quick, unrefined drawing may be defined as a sketch.