The idea is to dissociate the details of the object from the object itself, and instead look at the positive and negative spaces that construct our perception of it.
This is done without looking at the hand, pencil or paper in order to get a better sense of the curves and shapes of the object.
Five Minute Sketch
This sketch is done in a set time frame. The objective being to depict the object as accurately as possible in the given time.
Top View + Side View Elevations
These illustrations give an idea of the construction and layout of the object as seen from two matching perspectives 90º apart.