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 strategy and tactics
In a handicap game, Black starts with two or more handicap stones played before White's first move. If played in the traditional places on the "star points", these stones will be useful for the purpose of connection and separation of stones played closer to the edge ("lower"), as well as in many other ways. The White player's stones are threatened immediately with separation, while Black has many potential connections to begin with.