Sebaceous glands are microscopic
exocrine glands in the
skin that secrete an oily or waxy matter, called
sebum, to lubricate and waterproof the skin and
hair of
mammals. In
humans, they occur in the greatest number on the
face and
scalp, but also on all parts of the
skin except the
palms of the
hands and
soles of the
feet. The type of secretion of the sebaceous glands is referred to as
holocrine.