The Vocabulary of Line  
Line: “The path of a moving point, that is, a mark made by a tool
or instrument as it is drawn across a surface. A line is usually
made visible by the fact that it contrasts in value with the surface
on which it is drawn. "

calligraphy — derived from techniques of penmanship or writing, these lines are generally flowing and rhythmical.

calligraphic line quality — curvilinear, organic in feeling.

-------
contour — a line defining the outermost edge of an object or shape.

cross-contour — a line crossing over and defining surface undulations and 	information between the outer contours of images, areas, or shapes.

-------
physical properties of line — measure of the length and width.
	
type — straight, curved, zigzagged, etc.
	
direction — movement across the picture plane.
	
location — placement on the picture plane.
	
character — given by the medium used to make the line.

-------
hatching — repeated parallel strokes, lines, or clustered marks creating value. 
cross hatching — a second set of hatched lines in a different direction over the first, resulting in darker values. 

-------
mass — (1) graphic arts, the illusion of a solid body seeming to stand out 3-dimensionally–build up of line through hatching or cross hatching; (2) plastic arts, the physical bulk of material.

volume — A measurable quantity of unoccupied space that may recede spatially requiring different contrasts of hatching, value, line, etc.

-------
representation(al) art — art which presents the subject in a way that brings the actual objects to mind.

nonrepresentational art — defines work having non-recognizable imagery coming from objective origins (derived from nature but abstracted until the image is not recognizable) and ranging to nonobjective (not a product of the abstraction process, but derived purely from the artist’s mind).

plastic line — a line having spatial properties – advancing and receding. 

decorative line — a line remaining flat or embellishing the form. 

implied line (subjective lines) — lines that dim, fade, stop, and/or disappear and are visually completed or supplied by the viewer until the line reappears. 

-------
expression — the manifestation of an artistic idea or emotion (sometimes synonymous with content).