Condom can also be called a penis condom, mainly rubber or silicone materials made of one end of the closed, open end of the film-type products with rolled edges, as follows: First, during sex can be worn on the erect penis, so that semen can not enter the vagina and play a contraceptive role, and therefore called condoms. Secondly, the penis glans and vaginal mucosa can not be in direct contact, can significantly reduce the sensitivity of the penis glans, can significantly extend the time of sexual intercourse. Again, the penis and vaginal mucosa can not be in direct contact, can effectively prevent the transmission of genital herpes, warts, gonorrhea, syphilis and other sexually transmitted diseases.