Go opening strategy is the strategy applied in the game of go

Go (board game)

Go , is an ancient board game for two players that originated in China more than 2,000 years ago...

, in the early part of the game. On the traditional 19×19 board

Go (board game)

Go , is an ancient board game for two players that originated in China more than 2,000 years ago...

 the opening phase of the game usually lasts between 15 and 40 plies

Ply (game theory)

In two-player sequential games, a ply refers to one turn taken by one of the players. The word is used to clarify what is meant when one might otherwise say "turn"....

.

There are some conventional divisions that are applied. Firstly there is the distinction that may be drawn between go opening theory

Go opening theory

In the game of Go, the term opening theory refers to concepts which underlie where, why, in what order, and in what shapes the first several moves are played...

, the codified variations that resemble chess opening

Chess opening

A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...

s in the way that they occur repeated in games, and go opening principles. Since there is great freedom of choice, the fundamental opening principles are more useful for all players before they reach dan player

Go ranks and ratings

Skill in the traditional board game Go is measured by a number of different national, regional and online ranking and rating systems. Traditionally, go rankings have been measured using a system of dan and kyu ranks...

 level.

Basic principles

Examples of principles that are generally useful are comments such as 'corner-side-centre', which says that the corner areas of the board are more valuable than the sides (points near an edge but away from the corners). Occupying points in the centre may be good for early fighting, but these points are weaker from the aspect of developing one's territory.

Developments over the last century

The opening strategy in Go can be said to have undergone some major changes in the twentieth century. Not only have new joseki

Joseki

In Go, are studied sequences of moves in the corner areas of the Go board, for which the result is considered balanced for both black and white sides. Because games typically start with plays in the corners, players often try to use their understanding of joseki to gain local advantages in the...

been developed, but some important shifts in thinking have occurred. For example:

• from 1900 to 1930 the strategy was traditional, the so-called Shusaku style
• in 1933 and for a few years afterwards, a very different and experimental style called shinfuseki
  Shinfuseki
  or new opening strategy was the change of attitude to go opening theory that set in strongly in Japan in 1933. It corresponds, a little later, to hypermodern play in chess, with the inversion that shinfuseki thought the center of the board had been unjustly underemphasised.In the 1930s, a group of...
  
  dominated professional go, at least for the younger players
• from around 1936 there was a compromise of styles, sugou fuseki, which mixed some of the more successful ideas from shinfuseki with older techniques for a more balanced approach, forming the basis of modern professional play
• the introduction of komidashi
  Komidashi
  in the game of Go are points added to the score of the player with the white stones as compensation for playing second. Black's first move advantage is generally considered to equal somewhere between 5 and 7 points by the end of the game. Standard komi is 6.5 points under the Japanese and Korean...
  
  of 4.5 points in most top tournaments of the 1950s led to a tighter, territorial style for Black, for example in Sakata Eio, with greater use of the 3-3 point for White also.
• the Chinese opening dominated thinking from the early 1970s, and many further ideas were tried, for example the mini-chinese formation which is a side opening, rather than a corner opening or whole-board opening
• the entry of South Korea
  South Korea
  The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...
  
  n professionals into international competitions in the early 1990s saw the use of 'prepared variations' of whole-board openings, in a way not seen before.

Contemporary ideas

Contemporary Go opening strategy is more complicated than the old corner opening/whole-board opening distinction suggests. The 4-4 point is used by professionals in about 70% of corners. Corner openings for the 4-4 point are still being developed, but it is more accurate to say that almost all contemporary opening theory is implicated in the patterns around the 4-4 point.

Joseki

The Japanese term joseki, literally meaning "set stones", as in "set pattern" (jo means "fixed" or "set", and seki means stones), is the sequences of moves in game of Go, which results in a fair outcome for both black and white sides. Joseki, however, are not exclusive to the early game but can occur mid-game as well.

Fuseki

The Japanese term fuseki is sometimes taken as synonymous with 'whole-board strategy'. More accurately, it means the 'scattering' or thin distribution of stones that occurs in the early part of the game.