A condom is a device, usually made of latex, or more recently polyurethane, that is used during sexual intercourse. It is put on a male partner's penis, for the purpose of preventing pregnancy and/or transmission of sexually transmitted diseases (STDs) such as gonorrhea, syphilis and HIV.
Male condoms are packaged in a rolled-up form, and are designed to be applied to the tip of the penis and then rolled over the erect penis. They are most commonly made from latex, but are also available in other materials. As a method of contraception, condoms have the advantage of being easy to use, having few side-effects, and of offering protection against sexually transmitted diseases. With proper knowledge and application technique - and use at every act of intercourse - condom users experience only a 2% per-year pregnancy rate. Condoms may be combined with other forms of contraception (such as spermicide) for greater protection.