HPVs make up a group of more than 100 types of viruses. Most HPVs do no harm to a person. They are called papillomaviruses because they tend to cause warts, or papillomas. Warts are benign (noncancerous) growths. Different types of HPVs cause the warts that grow on the hands and soles of the feet, as well as those that grow on the mouth and genital area. The types of HPV that cause warts on the hands and feet do not cause genital warts. About 30 types of HPV are spread through sexual contact, causing infection and genital warts. These types of HPV can also cause cancer of the cervix (opening to the uterus, or womb) and other genital cancers. HPV is one of the most common causes of sexually transmitted disease (STD). And, 75 percent of people with HPV infection have no symptoms at all.