HPV stands for human papillomavirus, which is the most common sexually transmitted infection (STI) in the United States. There are more than 200 types of HPV, and about 40 kinds can infect the genital area, as well as the mouth and throat. HPV is usually harmless and goes away by itself, but some types can lead to cancer or genital warts. HPV is spread through intimate skin-to-skin contact, and a person with HPV can pass the infection to someone even when they have no signs or symptoms. Most people with HPV have no symptoms and feel totally fine, so they usually don’t even know they’re infected. Some HPV infections can lead to cancer, including cancers of the cervix, vagina, vulva, penis, anus, and back of the throat. HPV infections are often transmitted sexually or through other skin-to-skin contact, and vaccines can help protect against the strains of HPV most likely to cause genital warts or cervical cancer.