An Abscess in the skin caused by bacterial infection of a hair follicle which has spread and destroyed tissue beyond the anatomical boundary of the follicle (as opposed to a pimple, which is confined to the follicle). The central core of the boil, consisting of dead tissue and pus, is usually discharged onto the skin before healing begins. Because tissue destruction has extended beyond the skin boundary, a scar is left after healing. A blind boil is one in which the skin over the core of the abscess doesn't break down to release the pus. Surgical opening is usually necessary to prevent deeper spread of the infection. The pus discharged by a boil may spread to nearby or distant hair follicles resulting in clusters of, or recurrent, boils. For this reason it is best that the pus from a boil should be cultured to identify the bacteria causing the infection (usually staphylococci) and the appropriate antibiotic used to eradicate it.