Acne is commonly referred to as “pimples”, and what we often call acne, acne vulgaris, seborrheic dermatitis, rosacea, and rosacea are all extensions or evolutions of the concept of acne. Acne is the most common chronic inflammatory skin disease of the sebaceous glands of hair follicles. It is caused by blockage of sebaceous ducts and pores and poor outflow of sebum. During adolescent development, 80-90% of people will have acne on their face or other areas, only varying in severity. Virtually every age group has the potential to develop acne, which manifests itself as papules, blackheads, whiteheads, pustules, abscesses, nodules, cysts, and even scarring. Acne is a multifactorial disease that often has a genetic background. Factors such as increased secretion of androgens (e.g., dihydrotestosterone), blockage of follicular sebaceous glands or follicular opening keratinization, and microbial infections such as Propionibacterium acnes are the main causes of acne. The development of human sebaceous glands and sebum secretion are directly governed by androgens. During puberty, the level of androgens increases significantly, stimulating the sebaceous glands and making sebum secretion abnormally active. The lysozyme, proteolytic enzyme and hyaluronidase produced by Propionibacterium acnes can break down the triglycerides in sebum into free fatty acids. Some acne is caused by parasites or microbial infections such as worm mites, white staphylococcus, and Malassezia.