This page is a brief introduction to the game of go.
What is Go?
Go is similar in character to chess in that it is a game of pure skill (i.e. no chance element) played on a board marked in a grid pattern, with two players taking alternate moves. Both are highly respected games, and both are very old. Go is accepted as being close to 4000 years old, and according to legend was invented by an emperor of China to stretch the mind of his son, who may have been a bit on the slow side! It spread to Japan, and has been much developed in recent centuries there, becoming their national game and it supports approximately 400 professional players. The top players win many hundreds of thousands of ús each year. The game has only spread to the West this century, but it is steadily gaining in popularity.
How is it played?
The board is marked in a square grid, 19 lines by 19. The game starts with the board empty, and play consists of the two players taking it in turns to place counters called stones on grid intersections. One player has black stones, the other has white. Once placed, they do not move. The object is to surround the most territory, with each intersection representing one point of territory. It is also possible to capture opposing stones by surrounding them - this counts as extra territory. Play continues until both players pass, being unable to find a move to increase their own score or reduce their opponent's. The obvious comparison is with chess. Go is somewhat faster paced and less repetitive. Knowledge of standard openings/sequences is less important, and there is provision for a handicapping system which does not excessively distort the game. The rules are much simpler, and can be learnt within minutes. Consequently a total beginner can be playing and enjoying the game very quickly. However, the simplicity conceals the depth of the game; full time study by hundreds of professionals for centuries has not led to full understanding!
The big tournaments for professionals, with prize money of hundreds of thousands of pounds for the biggest, are based in East Asia and are sponsored by newspapers or other corporations. Most European countries have varying numbers of tournaments of various sizes, and each year there is a two-week "European Go Congress". In the UK, there are 15 to 20 tournaments each year, attracting anything from a couple of dozen players to well over a hundred for the London Open, which has a large contingent from Europe and beyond. The London Open and some other tournaments are sponsored.
At first sight, the game appears to lend itself to programming, and it is true that it is not difficult to write a programme that will play the game. However, the number of options for each move is much greater than for chess, so search trees get extremely long very quickly, and brute force is not enough even on supercomputers. The other problem is being able to decide, at the end of a potential sequence, whether it is good or not. It may be better locally but worse strategically. It is hard to programme in concepts of "good shape" or "bad style" or "power" or "potential". Considerable effort has been put into computer go, and the market in Japan, China, Korea and thereabouts for a good programme is very large; being similar to the number of chess games sold over here. In recent years, Google has also put a lot of effort into writing a computer go programme, as part of its research into AI, and in fact has been successful in developing something which can (and has) beaten the strongest professionals.
Want to know more?
There is a lot of information about the game on the web. A good start point is the British Go Association website.