International--Initiated by European architects--such as Mies van der Rohe--in the early 20th century, this is the style that introduced the idea of exposed functional building elements, such as elevator shafts, ground-to-ceiling plate glass windows, and smooth facades.
The style was molded from modern materials--concrete, glass, and steel--and is characterized by an absence of decoration. A steel skeleton typically supports these homes. Meanwhile, interior and exterior walls merely act as design and layout elements, and often feature dramatic, but nonsupporting projecting beams and columns. With its avant-garde elements, naturally the style appeared primarily in the East and in California.