Warts can be definitively diagnosed via examination by a physician; some physicians may take a biopsy of the wart and examine it under a microscope to ensure that it is a wart, according to WebMD. Warts come in many sizes and shapes, with some being smooth and flat and others exhibiting a rough-surfaced bump. Blood vessels supplying both regular and plantar warts appear as dark dots in the center of warts.
Common warts can occur anywhere on the body where the human papillomavirus enters and infects the skin's top layer, which usually happens via broken skin, according to WebMD. HPV causes the skin's top layer to experience rapid growth and wart formation. Many common warts grow on the hands and disappear on their own without any sort of treatment.
Genital warts are small red or pink growths that are found around the sex organs, notes the Cleveland Clinic. They may be difficult to see since they are tiny, and they may appear to look like small sections of cauliflower that are found in clusters of three or four and grow quickly. They may itch, bleed or cause mild pain, although the latter is not common. A physical examination by a physician is required to make a definitive diagnosis of genital warts.