After World War II, Wright was still thinking about how to design a house that many people could afford. He also wanted something that would improve the way people lived in the house. He achieved his goal by designing houses that used simple materials, built-in furniture, and standard units to make them easy to build. He made the houses interesting by using shapes other than squares for the floorplans. He experimented with rectangles, triangles, hexagons, and even circles. He made all the furniture out of plywood and cushions, and used built-in bookshelves and couches to reduce clutter. The walls were easy to disassemble and could be moved to accommodate changes in the clients' needs. These houses were called "Usonian" after the abbreviation for United States of North America.