Professional Go player who is known by the nickname "The Strong Stone." In February 2016, he ranked 2nd in the world in international Go world championship titles at 18. In March 2015, he competed against the computer AlphaGo in a 5-match contest, where he won 1 of the 5.
He began his professional Go playing career in the 1997-1998 season. He won his first professional match in 2000.
He has won over 400 matches of Go in his career. He earned the 9-dan rank in 2003.
He was born and raised in South Jeolla, South Korea.
His competing against the AlphaGo computer drew comparisons to Garry Kasparov's chess matches against the Deep Blue supercomputer in 1997.