Contour Line
Contour line drawing describes the touchable edges of an object; identifying the edges of every shift in plane with a line. There is no color, value, shading, or topical information included in this practice.

When working in this manner, it is helpful to slow down your observation. Look at your subject carefully and translate every curve and shift as you come to it, corresponding the movement of your hand with the movement of your eye. It is important to stop relying on your memory of what an object should look like, and start focusing on true observation and honestly recording the object in front of you.