A diaper (also called a nappy in South Africa, Ireland, United Kingdom, New Zealand, Australia and Zimbabwe) is a type of underwear that allows one to defecate or urinate, without the use of a toilet. When diapers become soiled, they require changing, generally by a second person such as a parent or caregiver. Failure to change a diaper on a sufficiently regular basis can result in skin problems around the area covered by the diaper.
Diapers are made of cloth or synthetic disposable materials. Cloth diapers are composed of layers of fabric such as cotton, hemp, bamboo or microfiber and can be washed and reused multiple times. Disposable diapers contain absorbent chemicals and are thrown away after use. Plastic pants can be worn over diapers to avoid leaks, but with modern cloth diapers, this is no longer necessary