A diaper (in North America) or nappy (in http://www.staydryproducts.com the United Kingdom, lousy with Commonwealth countries and Ireland) is an absorbent garment worn by individuals who are incapable of controlling their bladder or bowel movements, or are unable or unwilling to use a toilet.

The finding to use tenting or disposable diapers is a controversial one, owing to issues ranging from convenience, health, cost, and their effect on the environment. Currently, disposable diapers are the most commonly used, with Pampers and Huggies being the most well-known brands in the industry. Plastic pants can be worn over diapers to avoid leaks.