What are the differences between Chinese and Japanese rules in Go?
From Wikipedia:

Although there are some minor differences between rule sets used in different countries, most notably in Chinese and Japanese scoring rules, these differences do not seriously affect the tactics and strategy of the game.
There are two basic scoring systems used to determine the winner at the end of a game; they almost always give the same result. Territory scoring counts the number of empty points your stones surround, together with the number of stones you captured. While it originated in China, today it is commonly associated with Japan and Korea. Area scoring counts the number of points your stones occupy and surround. It is associated with contemporary Chinese play and was probably established there during the Ming Dynasty in the 15th or 16th century.

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