The body's outer layer that includes the skin, sebaceous glands, and sweat glands; whose functions are to protect the body against the invasion of bacteria and to aid in regulating body temperature and water content: Part of the integumentary system include the sebaceous glands that are small oil-producing glands in the skin which are usually connected to a hair follicle by a duct into which it releases sebum, a component of the slightly greasy film on the skin that helps keep it flexible and prevents too much water loss or absorption.

The glands are distributed over the entire body except the palms of the hands and the soles of the feet, most abundantly on the scalp and the face.