Warts are infections in the skin caused by the human papillomavirus (HPV). There are more than 100 types of HPV that are responsible for the many different types of warts, which include common warts, plantar warts, flat warts, and genital warts. Warts are common, particularly in childhood. Some estimates suggest that up to one in five children have warts, with children aged 12 to 16 years most commonly affected. Without medical treatment, many...