Go, known as 囲碁 in Japanese, 围棋 wéiqí in Chinese and 바둑 baduk in Korean, is an ancient board game for two players that originated in China more than 2,000 years ago. The game is noted for being rich in strategy despite its relatively simple rules.
The game is played by two players who alternately place black and white stones on the vacant intersections of a grid of 19×19 lines. Once placed on the board, stones cannot be moved elsewhere, unless they are surrounded and captured by the opponent's stones. The object of the game is to secure (surround) a larger portion of the board than the opponent. When a game concludes, the controlled spaces are counted to determine which portion is the largest, as exact territory size is not easily apparent during play. Games may also be won by resignation, if for example one side has suffered a severe tactical loss (too many stones captured, etc.).
Placing stones close together helps them support each other and avoid capture; on the other hand, placing stones far apart creates influence across more of the board. Part of the strategic difficulty of the game stems from finding a balance between such conflicting interests. Players strive to serve both defensive and offensive purposes and choose between tactical urgency and strategic plans. At its basis, the game is one of simple logic, while in advanced play the game involves complex heuristics and tactical analysis.
Go originated in ancient China sometime before the 3rd century BC (exactly when is unknown), by which time it was already a popular pastime, as indicated by a reference to the game in the Analects of Confucius. Archaeological evidence shows that the early game was played on a board with a 17×17 grid, but by the time that the game spread to Korea and Japan in about the 5th and 7th centuries respectively, the boards with a 19×19 grid had become standard.
The game is most popular in East Asia. In fact, 10% of all Koreans (North and South) play go, the highest percentage of all countries in the world. A conservative estimate places the number of Go players worldwide at approximately 27 million. Go reached the West through Japan, which is why it is commonly known internationally by its Japanese name.
Source and more about Go in general on Wikipedia.
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