Sebaceous glands are small, oil-producing glands located in the skin. They are connected to hair follicles and secrete an oily substance called sebum, which helps to keep the skin and hair moisturized. These glands are found all over the body, except for the palms of the hands and soles of the feet. The primary function of sebaceous glands is to protect the skin from drying out and to maintain its elasticity. Overactivity of these glands can lead to conditions like acne, while underactivity can result in dry skin. Proper skin care can help maintain the balance of sebum production.