Bedding, also known as bedclothes, refers to the materials laid above the mattress of a bed for hygiene, warmth, to protect the mattress, and for decorative effect. Bedding is the removable and washable portion of a human sleeping environment. Multiple sets of bedding for each bed will often be washed in rotation and/or changed seasonally to improve sleep comfort at varying room temperatures. In American English bedding generally does not include the mattress, bed frame, or bed base (such as box-spring), while in British English it does. In Antipodean English the term for bedding used is often Manchester. A set of bedding usually consists of (see #Terminology for more info on all these terms) a flat or fitted sheet which covers the mattress; a flat top sheet; either a blanket, quilt, or duvet, sometimes with a duvet cover which can replace or be used in addition to the top sheet; and a number of pillows with pillowcases, also referred to as pillow shams. Additional blankets, etc. may be added to ensure the necessary insulation in cold sleeping areas. A common practice for children and some adults is to decorate a bed with plush stuffed animals, dolls, and other soft toys. These are not included under the designation of bedding, although they may provide additional warmth to the sleeper.