It can be overwhelming to look at rows of condom boxes and not know if they all work equally well. The most important distinction to make between condoms is the material they’re made out of. Condoms can be made of latex, polyurethane or natural skin (or ”lambskin”). Some are sold as novelty items, which means they’re for fun, not protection; the packaging will say if they are meant for protection as well.

Be sure to buy only latex or polyurethane condoms. Only these types of condoms prevent the spread of sexually transmitted diseases (STDs). Most studies have been conducted on latex condoms, but for people who are allergic to latex, polyurethane is also a good choice.

Natural skin condoms do not protect against STDs because they have tiny pores (holes) that can allow STDs to pass through. They do protect against pregnancy, and some people use them only for that purpose.