What can a line do through a work of art?

Look at all the things lines do in this:

http://en.wikipedia.org/wiki/Image:Paul_Gustave_Dor%C3%A9_(1832-1883)_-_Baron_von_M%C3%BCnchhausen_(1862)_-_009.jpg

And here:
http://www.fws.gov/r9extaff/drawings/sgbirds.html
lOOK CLOSELY, and you will see it is all lines.

Lines can establish position, depth, shading, height, perspective, and in the two examples above, contours.

In a work of art, a line can serve various purposes and convey different meanings. Lines are one of the fundamental elements of art and can exhibit a wide range of characteristics, such as length, direction, curvature, and thickness. Here are several ways in which lines can be used in art:

1. Outline: Lines can define the outer shape or contour of an object, giving it form and structure.

2. Gesture: Quick, loose lines can capture the movement and energy of a subject, such as in figure drawings.

3. Implied lines: These are lines that are not physically present but are suggested by other elements in the artwork, guiding the viewer's gaze.

4. Expressive lines: Bold or jagged lines can evoke emotions or convey a particular mood, adding a sense of dynamism or tension to the artwork.

5. Lines of perspective: Using techniques such as converging lines, artists can create an illusion of depth and three-dimensionality in a two-dimensional artwork.

6. Cross-hatching and shading: By layering and intersecting lines, artists can create different values of light and shadow, adding texture and dimension to the art.

7. Contour lines: These are lines that describe the edges and surfaces of objects, providing details and aiding in the representation of form.

8. Geometric lines: Artists often incorporate geometric shapes and lines to convey order, symmetry, or structure within their composition.

To understand and appreciate how lines are employed in a specific work of art, closely observe the artwork and pay attention to the characteristics and placement of the lines. Consider how these lines interact with other elements, such as color, shape, and texture, to convey the artist's intended meaning or visual effect.