A shelf (pl. shelves) is a flat horizontal plane that is used in a home, business, store, or elsewhere to hold items that are being displayed, stored, or offered for sale. It is raised off the ground and usually anchored/supported on its shorter length sides by brackets. It can also be held up by columns or pillars. A shelf is also known as a counter, ledge, mantel, or rack. Tables designed to be placed against a wall, possibly mounted, are known as console tables and are similar to individual shelves.
A shelf can be attached to a wall or other vertical surface, be suspended from a ceiling, be a part of a free-standing frame unit, or it can be part of a piece of furniture such as a cabinet, bookcase, entertainment center, some headboards, and so on. Usually, two to six shelves make up a unit, each shelf being attached perpendicularly to the vertical or diagonal supports and positioned parallel one above the other. Free-standing shelves can be accessed from either one or both longer-length sides. A shelf with hidden internal brackets is termed a floating shelf. A shelf or case designed to hold books is a bookshelf.