Chests of drawers often come in 5-, 6-, and 7-drawer varieties, with either a single or a double top drawer. The chest illustrated at right would be described as a '5 over 2 chest-on-chest', the latter term deriving from the fact that at one time it would have been made as 2 separable pieces. They are commonly made of wood, similar to many other kinds of furniture, but of course can be made of other materials. The inside of the drawers can be accessed by pulling them out at the front side. It is often placed so that the back side faces a wall since access to the back is not necessary. The lateral sides are also usually made such that they can be placed against a wall or in a corner. Although they can be plain in appearance, chests of drawers can also be made with a fancy or ornamental appearance, including finishes and various external color tones. Traditionally, drawers would slide out on smooth wood rails. Most modern cabinets (such as Filing cabinets) use roll-out shelf sliders, made of metal, with rollers.