HPV vaccination prevents cancers and genital warts by protecting against common, high-risk HPV strains. The vaccine is most effective when given before sexual activity, ideally between ages 9-13, though recommendations extend up to age 26 for catch-up vaccination and can be discussed with a healthcare provider for ages 27-45. The series involves one or two doses for younger individuals and a three-dose series for older individuals, with no need for a booster shot