This is the line demarcating of “What is” and “What is not”. It is a boundary between what is perceived – seen – called. The positive shapes, and the space surrounding the perceived object called the “Negative shape”.
The contour line is a deceptively difficult line to draw well and a well drawn contour line rests upon sensitive and detailed persuasive information.
It is a line which has not only to express the edges of the figure but also suggest what conceals behind it.
This exercise has to make use of line in all its possibilities: