An 18-time champion retired because humans cannot beat at the game of Go. His is Lee Se-Dol. Mr Lee is the only in the world to beat Google's AlphaGo computer . This is an A.I. computer program to play Go. Mr Lee told that: "Even if I become the one, there is an that cannot be defeated. With the of A.I. in Go games, I've realized that I'm not at the ."
Go started in China 3,000 ago. Today, 46 people play it in 75 . It is the oldest game in the world. Mr Lee started playing at the of five. He turned when he was 12. He played five games against Google's AlphaGo and lost four of . He said he won because of a "bug". The did not know what to do when Mr Lee made a "tricky" . Today's Go programs are more than the one that beat Mr Lee.