Tables come in a wide variety of materials, shapes, and heights dependent upon their origin, style, intended use and cost. Many tables are made of wood or wood-based products; some are made of other materials including metal and glass. Most tables are composed of a flat surface and one or more supports (legs). Table tops can be in virtually any shape, although rectangular, square round and oval tops are the most frequent. Others have higher surfaces for personal use while either standing or sitting on a tall stool.