Go is a strategic board game for two players. It is known as in Chinese (Traditional: ; Simplified: ), or in Japanese (Kanji: or ), and in Korean (Hangul: ). In order to differentiate the game from the common English verb go, the game is sometimes written with a capital G or spelled as Goe, the latter used mainly in events sponsored by the Ing Foundation. Go originated in ancient China, centuries before its earliest known references in 5th century BC writing. It is mostly popular in East Asia but has nowadays gained some popularity in the rest of the world as well. Go is noted for being rich in strategic complexity despite its simple rules. Go is played by two players alternately placing black and white stones on the vacant intersections of a line grid. The standard size of this grid is 19 × 19, although the rules of Go can