Warts are harmless growths caused by a virus that infects the top layer of skin. Warts are often raised, rough and the same color as skin, but they can also be dark colored, flat or smooth. Warts most commonly grow on hands and feet, but they can appear anywhere on the body.
There are many viruses that cause warts, but they all fall under the category of human papillomaviruses (HPV). Unfortunately, though, the vaccine that protects against certain types of HPV infection won’t prevent most warts.
The viruses that cause warts are contagious, and warts can spread through direct skin-to-skin contact. You could even get warts if you touch a surface that’s been in contact with a wart.