Go, also known as Weiqi in Chinese and Baduk in Korean, is a game that originated in China about five thousand years ago. Two players, black and white, take turns placing a stone on a 19 by 19 board. The objective is to control a larger territory than the opponent. The rules are very simple; yet from simplicity comes endless complexity and strategic depth. Whereas the strongest chess programs can routinely defeat grandmasters, the strongest Go program can be defeated by a strong club player.