In the British Army, a private (Pte) equates to both OR-1 and OR-2 on the NATO scale, although there is no difference in rank. Privates wear no insignia. Many regiments and corps use other distinctive and descriptive names instead of private, some of these ranks have been used for centuries, others are less than 100 years old. In the contemporary British Armed Forces, the army rank of private is broadly equivalent to able seaman in the Royal Navy, aircraftman, leading aircraftman and senior aircraftman in the Royal Air Force, and marine (Mne) or bandsman, as appropriate equivalent rank in the Royal Marines. The term as a military rank seems to come from the Sixteenth Century when individuals had the privilege of enlisting or making private contracts to serve as private soldiers in military units.