The mammary gland is a specialized organ found in mammals, responsible for producing milk to nourish infants. These glands are composed of glandular tissue and are typically located in the breasts of females. In males, mammary glands are present but usually remain undeveloped. Mammary glands develop during puberty in females due to hormonal changes, primarily influenced by estrogen and progesterone. The milk produced contains essential nutrients, antibodies, and fats, making it vital for the growth and immune protection of newborns. The process of milk production and secretion is known as lactation.