A Petty Officer (PO) is a non-commissioned officer in many navies and is given the NATO rank denotion OR-5 or OR-6. In many nations, they are typically equal to a sergeant in comparison to other military branches. Often they may be superior to a seaman, generally they are lower ranks in a navy, and subordinate to a more senior non-commissioned officer, such as a Chief Petty Officer.
Petty Officers are from different branches,for example POMEM(Petty Officer Marine Engineering Mechanic), POHY(Petty Officer Hydrographer), POMA(Petty Officer Medical Assistant) POWS(UW)(Petty Officer Warfare Specialist (Underwater Warfare)).
