US Navy Petty Officer First Class Pin

Petty officer first class, PO1, is a non-commissioned officer rank in the Canadian Navy. It ranks above the rank of petty officer second class and its equivalents, and below the rank of chief petty officer second class and its equivalents. Its equivalent in the Army and Air Force is the rank of warrant officer (WO).

The United States Navy (abbreviated to US Navy or USN) is the navy of the United States of America, one of the armed forces of the federal republic.

Responsible for the conduct of naval military operations, its mission is "to maintain, train, and equip combat-ready naval forces capable of winning wars, deterring aggression, and maintaining peace at sea." In fiscal year 2015, it had 410,582 men and women on active duty and 132,000 in the Navy Reserve, operating 298 ships and more than 4,200 aircraft.

It traces its origins to the so-called Continental Navy, founded during the Revolutionary War and disbanded in 1790. The Constitution of the United States of America laid the foundation for the establishment of a navy by giving Congress the power to "provide and maintain a navy."

According to the reorganization of the US Navy conducted by Admiral Chester Nimitz, the fleets active in the Pacific are designated by an odd number, those active in the Atlantic and the Mediterranean by an even number.