A continuous mark made on a surface by a moving point; it may be flat (pencil line) or three-dimensional (a rod, groove, ridge, etc.) Line may be explicit - a line painted along the edge of the road - or implied by the edge of a shape or form. Lines are used to outline (diagrammatic or contour lines), create shading and show form (structural lines, hatching and cross-hatching), decorate, express emotion, and direct the viewer's eye.
