A deodorant is a substance applied to the body to prevent body odour caused by the bacterial breakdown of perspiration in armpits, feet, and other areas of the body. A subgroup of deodorants, antiperspirants, affect odour as well as prevent sweating by affecting sweat glands. Antiperspirants are typically applied to the underarms, while deodorants may also be used on feet and other areas in the form of body sprays.