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). A table with a single, central foot is a pedestal table. Long tables often have extra legs for support.
Table tops can be in virtually any shape, although rectangular, square, round (e.g. the round table), and oval tops are the most frequent. Others have higher surfaces for personal use while either standing or sitting on a tall stool.
Many tables have tops that can be adjusted to change their height, position, shape, or size, either with foldable, sliding or extensions parts that can alter the shape of the top. Some tables are entirely foldable for easy transportation, e.g. camping or storage, e.g., TV trays. Small tables in trains and aircraft may be fixed or foldable, although they are sometimes considered as simply convenient shelves rather than tables.
Tables can be freestanding or designed for placement against a wall. Tables designed to be placed against a wall are known as Pier tables or console tables (French: console, "support bracket") and may be bracket-mounted (traditionally), like a shelf, or have legs, which sometimes imitate the look of a bracket-mounted table.
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