Warts are generally harmless skin growths caused by a viral infection with Human Papillomavirus (HPV) in the top layer of the skin. Warts are spread by direct contact from person to person, sometimes indirectly. Scratching, or picking a wart can also result in the transfer of viral particles to another area of the skin.
Types of warts
1. Common warts：These warts usually grow on the fingers and toes, backs of the hands, knees and around the nails. They are most common where the skin has been broken. They generally look like a rough “warty” bump and may have a tiny black dot in the middle of each scaly spot.
2. Plane warts：These warts are smaller and smoother and tend to grow in large numbers, ranging from 20-100 at any one time. In children they are most common on the face, while in adults, they are often found in the beard area in men and on the legs in women. Shaving may lead to the spread of these warts.
3. Plantar warts：These are warts that grow on the soles (plantar area) of the feet and can often be flattened and pushed into the skin due to the pressure of walking. This can be painful, and feel like an uncomfortable stone in your shoe.