Warts are growths on the skin, usually on the hands or feet. Warts are caused by a contagious papilloma virus, which enters the body through breaks in the skin. Once inside the skin, the virus takes over the skin cells’ DNA, forcing them to create many copies of the virus. During this process, the skin cells multiply rapidly, creating a lump of cells which forms a wart on the skin. Watch this video to learn more about what’s causing your warts.