Contour Lines

A contour line is a detected line that demonstrates the border of an object on a space. Henri Gaudier-Brzeska's Study of a Small Boy shows the idea of a contour line through the rough sketch of the image. Although this is the final output of his idea, the sketch shows the border of the small boy.  It doesn't show a tremendous amount of detail.  All it does is clearly define where the boy is located on the space.