A wart is generally a small, rough tumor, typically on hans and feet, that can resemble a cauliflower or a solid blister. Warts are common, and are caused by a viral infection, specifically by the human papillomavirus (HPV) and are contagious when in contact with the skin of another. It is also possible to get warts from using towels or other objects. They typically disappear after a few months but can last for years and can recur.