This is short for Staphylococcus, a genus of micrococci bacteria with many members that can cause disease. They are gram-positive, nonmotile bacteria that are aerobic-(unless they need to be anaerobic). Staph of various types are responsible for boils and carbuncles; they may be involved in impetigo, toxic shock syndrome, endocarditis, osteomyelitis, and urinary tract infections, as well as some food poisoning.