Sketching is probably one of the oldest forms of visual brainstorming. The power of sketching stems from several advantages:

• It is possible to generate many ideas in a short amount of time.
• Sketching has minimal requirements--a writing instrument and a surface to sketch on. The proverbial napkin is a famous example. The range of possibilities, from a pencil and paper to mobile apps, is very wide.
• It can be done almost anytime, anywhere.
• No need to be a celebrated illustrator--rough and basic sketches can do the job. It is easy to add notes to clarify.
• It is easy to show, share, and come up with new variations.
• Sketching is cheap.

The following image includes sample sketches dating from the 15th century. It may seem that these examples are very much in contrast to the list above, since today these sketches are considered to be works of art in their own right. Yet, while scribbled by extremely gifted people, they were not created as artwork, but rather, as quick sketches meant to help idea development.

• Leonardo Da Vinci's exploration of a device for lifting weights (A)
• Michelangelo's sketch of the Dome of the St. Peter Cathedral, for which he was, at some point, the chief architect (B)

Sketching works well to explore forms, proportions, configurations, and transformations. The following image includes a number of sketching artifacts--samples of usage in architecture (A), automotive design (B), package design (C), and web design (D).

The use of these artifacts is typically limited to the designer and is not an expected deliverable. It is an exercise that allows the designer to flesh out some of the core visual properties that the product will express through its physical shape as a three-dimensional object or as a page--digital or printed. As a communication tool, sketching helps discuss the structure and organization of layouts and content, user journeys, and task flows, almost anything, really.