Aim of the game
The aim of Go is to capture more territory and prisoners than your opponent.
Start of the game
The game is played on a grid of points (15x15 by default). A Go move is played on the intersections of the lines. The black player moves first.
During a Go game one or more stones can be captured by completely surrounding them on four sides, i.e. filling all empty points around them. During a Go game one or more stones can be captured by completely surrounding them on four sides, i.e. filling all empty points around them. If a move would result in the same board pattern that existed before the opponent's move, the player is required to abstain from that move and make a move elsewhere. This situation is known as a KO (the knot). This rule is used to prevent stalemates and endless repetition.
End of the game
A player may pass instead of placing a stone. When both players pass consecutively, negotiation will begin and both players shall mark dead stones. A player's score is the number of empty points enclosed only by his stones (territory) plus the number of captured stones (prisoners). The player with the higher score wins.
Check the FAQ for more information.