A bed is a piece of furniture used as a place to sleep or relax. It has a secondary use as a location to engage in sexual relations.
Most modern beds consists of a mattress on a bed frame, with the mattress resting either on a solid base, often wooden slats, or a sprung base. In North America many beds include a box spring inner-sprung base, a large mattress-sized box containing wood and springs that provide additional support and suspension for the mattress.
Most beds have a headboard for resting against, with others also having side rails and footboards (or "footers"). "Headboard only" beds often incorporate a "dust ruffle", "bed skirt", or "valance sheet" to hide the bed frame.
For greater head support, most people use a pillow, placed on the top of a mattress. Also used is some form of covering blanket to insulate the sleeper, often bed sheets, a quilt, or a duvet, collectively referred to as bedding. Bedding is the removable non-furniture portion of a sleeping environment. A bed can be thought of as a body, and the bedding its clothing.
Also, some people prefer to dispense with the box spring and bed frame, and replace it with a platform bed style. This is more common in Europe, Australia and Japan.