Marine Corps Officers are assigned to many Military Occupational Specialties (MOSs) which fall under three main categories: Ground, Air, and Law.
Ground: the majority of Marines operate in ground specialties, in roles ranging from infantry to combat service support.
Air: Marine Pilots and Naval Flight Officers train on jets, helicopters, tilt-rotor aircraft, and turboprop aircraft.
Law: training for Judge Advocates supplements a law degree, with instruction for practicing law in the military. Please see Roles In The Corps for more information.