The Republic of Korea Navy (ROKN), also known as the ROK Navy, is the naval warfare service branch of the South Korean armed forces, responsible for conducting naval operations and amphibious landing operations. The ROK Navy includes the Republic of Korea Marine Corps, which is a quasi-autonomous organization. Established in 1945, the ROK Navy is the oldest branch of the South Korean armed forces.
Since the end of the Korean War, the South Korean navy has concentrated its efforts to building naval forces to counteract the North Korean navy, which has littoral naval capabilities. As South Korea's economy grew, the ROK Navy was able to build larger and better equipped fleets to deter aggression, to protect national maritime rights and to support the nation's foreign policy. As a part of its mission, the ROK Navy has engaged in several peacekeeping operations since the turn of the 21st century.
The ROK Navy aims to become a blue-water navy by 2020.
The ROK Navy employs the U.S. Navy-style letter based hull classification symbols to designate the types of its ships and hull numbers to uniquely identify its vessels (e.g. DDH 975). The names are that of the historical figures, provinces, cities, counties, peaks, lakes, islands, and birds. The Chief of Naval Operations selects the names of ships.
There are four ship ratings. A first-rate ship (DDG, DDH, Sohn Won-yil class SS, LPH, MLS, AOE, and ASR) is commanded by a captain; a second-rate ship (FF, SS, PCC, LST, and ATS) by a commander; a third-rate ship (SSM, PKG, MSH, and MHC) by a lieutenant commander; and a fourth-rate craft (PKM and LSF) is commanded by a lieutenant or a warrant officer.
The ship prefix for all the commissioned ROK Navy ship is ROKS (Republic of Korea Ship) when the names of ships are written in English.