It is widely accepted among schools, art institutions, and colleges as an effective training aid and discipline[3] for beginner artists.
In the hands of a talented master, the line that conveys contour can deliver an astonishing amount of visual delight.
[4] By altering the character of the mark, an artist can emulate many aspects of the subject that relate form and space to the viewer.
For example, a line can be lighter in value (gradation) to suggest greater distance between objects in the drawing.
Initially, this type of drawing may be difficult and slow, but an artist will find that with practice, it is an effective way of defining observation skills such as identifying and underlying the structure of the subject, relating forms, and conveying the sensual experience of the subject.