A condom is a type of contraceptive device that is used during sexual activity to prevent pregnancy and the transmission of sexually transmitted infections (STIs). It is typically made of latex, but there are also condoms made of polyurethane or natural materials like lambskin. Condoms work by creating a barrier between the penis and the vagina, preventing the exchange of bodily fluids that can lead to pregnancy or the spread of STIs. They are available in various sizes, shapes, and textures, and can be lubricated or non-lubricated. Condoms are widely available for purchase without a prescription and are considered one of the most effective methods of birth control when used correctly and consistently.