One of the foremost practitioners of Minimal Art, Donald Judd is best known for his sleek, boxlike constructions made of industrial materials such as aluminum, plywood, sheet metal, and plexiglass. Through these works, he sought to create a depersonalized art in which the exploration of space, scale, and materials served as an end, rather than as a metaphor for human experience. Emphatically concerned with pure forms, Judd's works become statements about proportion and rhythm as well as three-dimensional space. His stacked boxes seem to come directly out of the wall rather than projecting from a backing surface. This creates the impression that the artwork shares the observer's space instead of being set apart like a sculpture on a pedestal.