Buttress  A support, usually exterior, for a wall, arch, or vault, that opposes the lateral forces of these structures. A flying buttress consists of a strut or segment of an arch carrying the thrust of a vault to a vertical pier positioned away from the main portion of the building. An important element in Gothic cathedrals.

Composition  The bringing together of parts or elements to form a whole; the structure, organization, or total form of a work of art. See also design.

Calligraphy  The art of beautiful writing. Broadly, a flowing use of line, often varying from thick to thin.

Color Field Painting  A movement that grew out of Abstract Expressionism, in which large stained or painted areas or "fields of color" evoke aesthetic and emotional responses.