A two-dimensional area having identifiable boundaries created by lines, color of value changes or some combination of these; broadly, form. See Form.<br><br>An element of art, it is an enclosed space defined and determined by other art elements such as line, color, value, and texture. In painting and drawing, shapes may take on the appearance of solid three-dimensional object even though they are limited to two dimensions; length and width. This two-dimensional character of shape distinguishes it from form, which has depth as well as length and width.Examples of shapes include: circle, oval, and oblong; polygons such as triangle, square, rectangle, rhombus, trapezium, trapezoid, pentagon, hexagon, heptagon, octagon, nonagon, decagon, undecagon, dodecagon, etc.; and such other kinds of shapes as amorphous, biomorphous, and concretion.Also see angle, curve, edge, egg-and-dart, flat, fold, French curve, letterform, manipulate, memory, obverse and reverse, positive and negative space, radial, straight, structure, surface, and vertex.