The rules of go have seen some variation over time and from place to place. This article discusses those sets of rules broadly similar to the ones currently in use in East Asia. Even among these, there is a degree of variation.
Notably, Chinese and Japanese rules differ in a number of aspects. The most significant of these are the scoring method, together with attendant differences in the manner of ending the game.
While differences between sets of rules may have moderate strategic consequences on occasion, they do not change the character of the game. The different sets of rules usually lead to the same game result, so long as the players make minor adjustments near the end of the game. Differences in the rules are said to cause problems in perhaps one in every 10,000 games in competition.
This article first presents a simple set of rules which are, except for wording, identical to those usually referred to as the Tromp–Taylor Rules, themselves close in most essential respects to the Chinese rules. These rules are then discussed at length, in a way that does not assume prior knowledge of go on the part of the reader. The discussion is for the most part applicable to all sets of rules, with exceptions noted. Later sections of the article address major areas of variation in the rules of go, and individual sets of rules.
A set of rules suitable for beginners is presented here. In some respects, these differ from the rules most commonly used. However, the basic rules are simply stated, and provide a convenient basis on which to discuss differences in rulesets. The rules are studied more fully in § Explanation of the basic rules below.
Two statements of the same basic rules, differing only in wording, are given here. The first is a concise one due to James Davies. The second is a formulation of the basic rules used for expository purposes in this article.
Except for terminology, the basic rules are identical to the Logical Rules first proposed in their current form in September 1996 by John Tromp and Bill Taylor. They are also quite close to the Simplified Ing Rules of the European Go Federation, the only exception being the method of ending the game.
These rules appear in "The Rules and Elements of Go" by James Davies. They assume familiarity with the equipment used to play go, for which one may refer to § Elements of the game below.
Notes: The words move and territory are used differently here than elsewhere in this article; play and area, respectively, are used instead. A clarification to rule 5 is added in parentheses.