Admiral Yi Sun-sin.

Yi Sun-sin (1545–1598) was a Korean naval commander, famed for his victories against the Japanese navy during the Imjin war in the Joseon Dynasty, and is well-respected for his exemplary conduct on and off the battlefield not only by Koreans, but by Japanese admirals as well. Military historians have placed General Yi Sun-Sin on par with Admiral Horatio Nelson as arguably the greatest naval commander in history for his undefeated record against seemingly insurmountable odds despite no background in naval training. Yi remains a venerated hero among Koreans today.

Perhaps his most remarkable military achievement occurred at the Battle of Myeongnyang. Outnumbered 133 warships to 13, and forced into a last stand with only his minimal fleet standing between the Japanese Army and Seoul, he still managed to leave 31 of the 133 Japanese warships either destroyed or impaired, without losing a single ship of his own.

Value and "Bank of Korea" in Hangul.

The Korean alphabet, known as Hangul in South Korea (also transcribed Hangeul) and as Chosŏn'gŭl/Chosŏn Muntcha in North Korea and China, is the alphabet that has been used to write the Korean language since the 15th century.