Mattress is a large pad for supporting the reclining body, used as a bed or as part of a bed. Mattresses may consist of a quilted or similarly fastened case, usually of heavy cloth, that contains hair, straw, cotton, foam rubber, etc., or a framework of metal springs. Mattresses may also be filled with air or water.
Mattresses are usually placed on top of a bed base which may be solid, as in the case of a platform bed, or elastic, e.g. with an upholstered wood and wire box spring or a slatted foundation.
Popular in Europe, a divan incorporates both mattress and foundation in a single upholstered, footed unit. Divans have at least one innerspring layer as well as cushioning materials. They may be supplied with a secondary mattress and/or a removable “topper.”
Mattresses may also be filled with air or water, or a variety of natural fibers, such as in futons. Kapok is a common mattress material in Southeast Asia, and coir in South Asia.