Everything About Fiction You Never Wanted to Know.
    A game of Go in progress.

    Go is a board game for two players, noted for being rich in strategic complexity despite its simple rules. It is known in Japan as 碁 or 囲碁 (Go or Igo), in China as 围棋 (Weiqi), and in Korea as 바둑 (Baduk). Go reached the West through Japan, which is why it is commonly known internationally by its Japanese name, and much of its technical vocabulary is Japanese.

    The game is played by two players who alternately place circular black and white pieces called "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 control a larger area of the board than the opponent.

    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.

    The origins of Go are Shrouded in Myth. It originated in China more than 2,500 years ago, and although it is not known exactly when the game was invented, by the 5th century BC it was already a popular pastime. The oldest surviving written reference is in the Analects of Confucius (c. 500 BCE) by which time the game was already well-known. Archaeology suggests an origin somewhere in the 2nd millenium BCE, so Go is probably Older Than Dirt. Archaeological evidence indicates 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 7th century, the 19x19 board had become standard. The game is most popular in East Asia, but spread to other parts of the world. A conservative estimate places the number of Go players worldwide at approximately 27 million.

    If you want a cursory animated introduction, try watching Hikaru no Go, which may have inspired many to play Go. For much more information check either the other wiki or visit Sensei's Library, a wiki devoted to the game.

    Essays have been written about the differences between Go and Chess. Note that a former world champion of chess stated that Go was so universal in its simple complexity that he wouldn't be surprised if there were extraterrestrials who knew Go.

    Not to be confused with the 1999 film Doug Liman film Go, the short-lived early '80s television game-show, the travel-themed family board-game published by Waddingtons, or the programming language developed by Google.

    Sometimes used as the game of choice for the trope Smart People Play Chess.

    Tropes used in Go include:

    • Artificial Stupidity: Played straight to begin with, but averted by the mid-2010s.
      • As of 2012, the best commercial Go-playing computer programs were roughly on a par with fairly strong amateurs. Really strong professional players were still well beyond their reach.
      • The best computer programs can beat pros on the 9x9 board, and that size is slowly increasing.
        • However the computer used close to five times more time than the professional and only won one game out of three. The problem is that it gets exponentially harder as the board size increases. To the point where professionals still beat computers on 19x19 boards, even when the computer has a 9 stone handicap.
        • As of 2012, however, a computer has recently beaten a famous professional named Takemiya Masaki with only a 4-stone handicap, which seems to indicate an increase in the playing level of the best computer programs.
      • In 2016, Google-designed AlphaGo achieved a 4-1 victory over one of the world's top players, Lee Sedol, eventually leading him to Rage Quit the game three years later.
        • One year after AlphaGo's victory, its successor AlphaGo Master achieved an unbroken 60 game winning streak against top players, then beat a team of five top players working in unison.
          • And then AlphaGo Zero learned the game from first principles and beat AlphaGo 100 games in a row.
      • In 2022, a Chinese Go player was suspended for a year 'for using AI' in a tournament. The article doesn't identify which AI the player used.
    • Broken Base: Despite its antiquity, the rules of Go are mostly the same everywhere, but there are technical differences between the rules used in China, and those in Japan and Korea, mostly concerning the way the score is calculated, but also how a few very rare situations are handled.
    • Crazy Prepared: Serious players study and memorise many sequences of best play, known as joseki. Strong players can usually reel off entire games from memory.
    • Flipping the Table: A traditional (if humorous) way to Rage Quit is known as the "nuclear tesuji," where the losing player flings the board at the wall, uppercuts the winner and storms out. (Troper General's Warning: Don't actually try this, it's not considered good sportsmanship anymore.)
    • Idiosyncratic Episode Naming: Some famous games have exotic titles like "The Ear-Reddening Game", and probably most famous of all, "The Blood-Vomiting Game" (See Serious Business below).
    • Kyu and Dan Ranks: Go players are ranked according to their playing strength. Complete beginners are ranked at roughly 30-35 kyu (30-35k), and as they improve, their rating reduces, so a 10k player is stronger than a 15k player. This is because kyu ranks are based on the number of handicap stones players would need to win half their games against a First Dan player (See PVP-Balanced below), and the stronger player needs a smaller handicap. After winning promotion to First Kyu (1k), the highest kyu rank, the next step is Shodan or First Dan (1d), and dan ranks rise with greater strength from First to Ninth Dan, the highest amateur rank. Professional players have their own ranking system, rising from First (1p) to Ninth (9p) Dan. Go may have been the first game or sport to use the kyu/dan system.
    • Metagame: Thousands of pages of analysis have been written over the centuries. The only game with a comparable literature is Chess.
    • Play-By-Post Games: Nowadays internet Go servers, and e-mail, have largely replaced this. Playing Go on-line brings many Video Game tropes with it, including:
      • Scrub: Some players feel entitled to assume that their way is the only legitimate way to play, and anything else is cheating. The particularly applies to the choice of Japanese vs. Chinese rules and scoring.
      • "Stop Having Fun!" Guys: Because Go is Serious Business.
      • Rage Quit: Some players abandon losing games without resigning to avoid having the loss affect their rank on the server. This is known as "escaping", and the way in which "escapers" are handled by some Go servers is controversial.
      • Also, a little trick for those bored in class: take a math notebook page, mark the borders of the board on the page’s square, take two pencils and erasers to mark the stones and score, pass the page between players, and voilà, classroom Go!
    • Pronoun Trouble: When writing about Go (in the abstract rather than when referring to specific players), it is customary to refer to one player as "he" and the other as "she". Unfortunately some believe black should be male, and white female, while others appeal to ancient Taoist tradition and argue for the opposite.
    • PVP-Balanced: Enormous attention is given to giving both players an even chance:
      • Although each player has identical resources, black customarily plays first, which gives him an advantage. In a game between equally-strong players, white receives an scoring allowance called komi to compensate her for this. The exact size of komi is periodically adjusted based on exhaustive analysis of professional game statistics.
      • In a game between players of different strength, the weaker player takes black, and komi may be reduced or eliminated. If the difference in strength is sufficient, black may also be allowed to place a number of "handicap stones" on the board before the game begins, to give him a head start. The idea is to allow both players to share an enjoyable game, so the size of the handicap is adjusted to their respective playing strengths. This leads to differences in playing strength being expressed in terms of "stones", as in: "Ben is four stones stronger than Bill". The handicap is traditionally calculated by comparing the players' Kyu and Dan Ranks (see above).
      • Japanese rules require the handicap stones to be placed on specific points, the first nine of which are normally marked on the board as the hoshi (star) points. Japanese rules specify patterns for handicaps of up to seventeen stones, but various unofficial patterns have been published for handicaps of up to forty-one stones, the traditionally-accepted difference between a complete beginner and the strongest amateur player. Chinese rules allow free placement of handicap stones, so potentially there is no limit to the size of handicap that could be given.
      • An alternative to very large handicaps is to play on a smaller board (13x13 and 9x9 being by far the most common sizes). Handicap stones have a much greater effect on a smaller board (a common rule of thumb is that one handicap stone on 13x13 is approximately equivalent to three in 19x19), so the game can be played evenly without the need for so many of them, making the play more sensible.
    • Serious Business: Oh so very much:
      • Full-time professional players competing for multi-thousand dollar prizes.
      • Well-attended after-school classes for school-children.
      • Full-time students studying for examination tournaments to qualify to become professionals.
      • Extensive television coverage of pro games, including dedicated channels!
      • Pro games lasting up to sixteen hours over two days (they used to be much longer).
      • Unwritten but deeply-rooted conventions of proper behaviour and play, over which there is much discussion.
      • As the board was being cleared after the legendary four-day "Blood-Vomiting Game" of 1835, the defeated player Akaboshi Intetsu, collapsed coughing up blood, and died ("within a few months" though).
      • In Ancient China, a Go game that ended badly started a war: the Crown Prince of Han invited his cousin over to play. When he lost he threw the goban at the cousin, killing him (perfectly possible; a traditional goban can weigh as much as twenty kilos (forty pounds)). The cousin's grieving father declared war over the breach of hospitality.
    • Tournament Play: Professional tournaments are regarded as the highest form of the game by many players, and success in them is essential to the careers of pro players. Amateur national rankings are also based on performance in tournaments.
    • Why Mao Changed His Name: The Chinese name for the game is 围棋. This used to be romanised as wei-chi, but since the adoption of pinyin romanisation, it is written weiqi. The correct pronunciation remains (roughly) "way-chee".