Practically everyone has HPV, and most of the time we don't even know it. It's the same virus that causes warts. Not just the genital kind, but the garden variety warts.
There are many strains, but only a couple that are serious. It's a problem if it leads to cervical cancer, but rarely in the U.S. does cervical cancer get very far. In the developing world, it's one of the leading causes of death for women. It's also the only cancer that is 100% curable if caught early, which is why women get Pap tests so often.