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)
"Dame" are points that lie in between the boundary walls of black and white, and as such are considered to be of no value to either side. "Seki" are mutually alive pairs of white and black groups where neither has two eyes. A "ko" (Chinese and Japanese: ) is a repeated-position shape that may be contested by making forcing moves elsewhere. After the forcing move is played, the ko may be "taken back" and returned to its original position. Some "ko fights" may be important and decide the life of a large group, while others may be worth just one or two points. Some ko fights are referred to as "picnic kos" when only one side has a lot to lose. The Japanese call it a hanami (flower-viewing) ko.