Go (game)
Two players, "Black" and "White", take turns placing a "stone" (game piece) of their own color on a vacant "point" (intersection) of the grid on a Go board. Black plays first. If there is a large difference in skill between the players, the weaker player typically uses Black and is allowed to place two or more stones on the board to compensate for the difference (see Go handicaps). The official grid comprises 19×19 lines, though the rules can be applied to any grid size. 13×13 and 9×9 boards are popular choices to teach beginners, or for playing quick games. Once placed, a stone may not be moved to a different point.
Go (game)
A player may pass on determining that the game offers no further opportunities for profitable play. The game ends when both players pass, and is then scored. For each player, the number of captured stones is subtracted from the number of controlled (surrounded) points in "liberties" or "eyes", and the player with the greater score wins the game. Games may also be won by resignation of the opponent.