A boil is a skin infection that starts in a hair follicle or oil gland. At first, the skin turns red in the area of the infection, and a... A boil is a skin infection that starts in a hair follicle or oil gland. At first, the skin turns red in the area of the infection, and a tender lump develops. After four to seven days, the lump starts turning white as pus collects under the skin. • The most common places for boils to appear are on the face, neck, armpits, shoulders, and buttocks. When…