Venereal disease (venerealdisease) is traditionally thought of as a disease transmitted through the act of sexual intercourse, with the primary lesion occurring in the genital area. They include syphilis, gonorrhea, soft chancre, venereal lymphogranuloma, and inguinal granuloma. STDs are a group of common infectious diseases widely prevalent in the world, and show a trend of expanding epidemic scope, decreasing age of onset, and increasing drug-resistant strains, especially the significant increase of AIDS, which has become a serious public health problem. The prevention and treatment of sexually transmitted diseases will be a very difficult and long-term task. STD is the abbreviation of sexually transmitted diseases, the modern concept refers to a group of systemic infectious diseases transmitted mainly through sexual contact. The old concept of venereal disease, also known as “phimosis”, refers to a variety of systemic diseases transmitted through sexual intercourse, with obvious damage to the genital organs, usually including only syphilis, gonorrhea, soft chancre, venereal lymphogranuloma and inguinal granuloma and other five diseases, they are also known as “classical STDs”, from the 1970s, the diseases included in STDs gradually increased, and in 1975 the World Health Organization (WHO) officially decided to use the name of sexually transmitted diseases (STDs) to replace the concept of STDs, which include more than 20 kinds of diseases. 2, STDs are a group of systemic diseases Although most STDs have obvious damage to the reproductive organs, many STDs can affect multiple systems and organs throughout the body, and some do not even have obvious damage to the reproductive organs. So do not think that STD only genital lesions. 3, STD does not refer to the genitourinary system of all diseases STD is a group of infectious diseases, and genitourinary system of STD is only a very small part of all diseases of genitourinary system. Do not say all the diseases of the genitourinary system are STDs. Some people have observed the skin mucous membrane with genital area abnormalities in the skin venereal disease department outpatients, found that more than half of the patients are non-STD damage. 4, venereal disease does not include sexual dysfunction sexual dysfunction is a group of diseases that can not carry out normal sexual activity or pregnancy and childbirth, such as impotence, premature ejaculation, sexual coldness, infertility, premature birth, sometimes Chinese medicine will be sexual dysfunction as “venereal disease”, but never the venereal disease referred to here. Although venereal disease can cause sexual dysfunction, but venereal disease is a group of infectious diseases, not including sexual dysfunction. 5, sexual contact is not only refers to sexual intercourse sexual intercourse is generally refers to penile penetration of the vagina a sexual contact behavior. Sexual contact capable of transmitting diseases includes close skin-to-skin contact between all individuals, and they may be normal, abnormal, pathological, homosexual, such as anal sex, oral sex, kissing, etc. 6, STDs are not all transmitted by sexual contact STDs are mainly transmitted directly through sexual contact, accounting for more than 95%, but there are still a small number of contact with the patient’s secretions, blood-contaminated items and infection, that is, indirect transmission, including the same bed, the same bath tub, sharing bath towels, clothing, towels, toilets, injection needles, etc., some people call “innocent STDs Some people call it “innocent STD”.