Plantar warts are hard warts that develop on the sole of the foot, caused by HPV strains 1 and 2. These strains enter through small cuts or abrasions and thrive in warm, moist environments like the sole of the foot. Plantar warts grow deep inside the skin, are initially painful with black pinpoints, and have a rough, scaly texture. While they can sometimes be mistaken for corns or calluses, plantar warts are highly contagious and spread through direct contact with the virus. Treatment options include surgery, cryotherapy, chemicals, electricity, or laser therapy but they may also go away without treatment if not too painful.