Warts are not skin allergies. It is actually a viral infection by the human papilomavirus (HPV), which is contagious and can spread through the use of towels, and skin contact. It usually disappears over time, but can recur.

Warts are categorized according to its shape, size and location in the body, and the type of HPV. The types of warts are: common wart, flat wart, digitate wart, plantar wart, mosaic wart and genital wart. Common wart appears mostly on the hands and knees. Flat wart on the face, neck, hands and knees; digitate wart is usually protruding, on the face, near the lips and eyelids; plantar warts are dark and occurs on pressure points like the soles of the feet. Mosaic wart is in clusters, and genital wart occurs in the genitalia.

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