According to the secretion of sebaceous glands and skin sensitivity, the skin can be divided into the following five types: 1, neutral skin: sebaceous glands secretion moderate, also known as normal skin. The skin is white and red, lubricated and lustrous, fine, fine pores, elastic, and low sensitivity to external stimuli. 2, dry skin: sebaceous gland secretion less, also known as dry skin. The skin is dry, thin skin, no luster, poor skin elasticity, the face is easy to produce small wrinkles, pores are not obvious, poor tolerance to external stimuli. 3, oily skin: sebaceous glands secrete a lot, also known as poly-lipidic skin. The skin is oily and shiny, with good skin elasticity, not easily wrinkled, but with large pores, easy to acne, and strong tolerance to external stimuli. 4, mixed skin: both dry and oily skin characteristics, generally in the forehead, nose, nasolabial folds and other parts of the performance of oily skin, in the cheeks for dry skin. 5, sensitive skin: also known as allergic skin, this type of skin is highly sensitive, often accompanied by other systemic allergic diseases, more sensitive to a variety of stimuli in the internal and external environment, after contact with allergic symptoms such as erythema, papules, itching.