Boils start as an infection and develop as a soft lump. After four to seven days, the lump turns white and pus collects under the skin. Boils most commonly appear on the face, neck, armpits, shoulders, and buttocks. When a boil forms on the eyelid, it is called a stye, and sometimes boils can appear all over the body.

Impetigo is a common superficial bacterial infection of the skin, characterised by vesicles that rapidly become purulent and then rupture, leaving shallow erosions and honey-coloured crusts. The term impetiginisation is used to describe superficial secondary infections of a wound or skin condition. When the lesion ulcerates deeply it is called impetigo.