Go
Take turns placing stones on the crossings. Surround empty points and capture stones that run out of liberties. When both players pass, the side with more area wins.
Also try Gomoku → Also try Hex →
How to play Go
How to play
Black moves first, then you take turns placing one stone on any empty crossing. Stones never move. The empty points next to a group of connected stones are its liberties: a group whose last liberty is filled is captured and taken off the board. You may not play a stone that would have no liberties unless it captures, and you may not repeat an earlier position of the whole board, which settles a ko fight.
Ending and counting
When neither side can gain more, press Pass. Two passes in a row end the game. The computer then crosses out the stones it thinks are dead and shows each side's area. Tap a group to change that, then press Accept count. If you claim stones dead that the computer thinks are alive, or the other way round, choose Play on: the game continues, and when both pass again every stone left on the board counts as alive.
Scoring
This is area scoring: you get one point for each of your stones on the board and each empty point that only your stones surround. Captured stones don't count separately. White receives komi for moving second: 7.5 points on 9×9 and 8.5 on 7×7, where careful analysis suggests Black wins by 9 with best play. The half point means there are no ties.
The computer
The computer plays out many quick random games from the position and picks the move that does best in them. Easy plays out 160 games per move (120 on 7×7), and on 9×9 it gives you two handicap stones when you play black, with komi 0.5. Medium plays out about 1,000 and Hard about 3,000 to 4,000. Within a game the same position always gets the same reply, on any device. Use Play second to let it open as Black.
Questions
What is komi in go?
Komi is the points White gets for moving second, because the first move is an advantage. Here it is 7.5 on 9×9 and 8.5 on 7×7, and 0.5 in handicap games. The half point decides a game that would otherwise be tied.
What does ko mean in go?
Ko is a shape where each side could capture one stone back and forth forever. A play may never repeat an earlier position of the whole board, so after the other side takes a ko you must play somewhere else first before you can take it back.
How do you know when a go game is over?
When every point is clearly someone's and any stone you add would gain nothing, pass. If the computer passes too, the game ends and you agree on dead stones before the count. You can always choose Play on if you want to keep playing.
Why is 9×9 good for learning go?
A 9×9 game takes minutes instead of an hour, yet it has everything that makes go: capturing, life and death, ko and counting. Many players learn there and move to 13×13 and 19×19 later. 7×7 is even quicker for a first game.
How does the hint work?
It runs a longer search for your side, rings the point and says one true thing about it: it captures, saves a group in atari, puts the computer's stones in atari, connects your groups, takes a liberty, or is simply the search's favourite. When nothing is left to gain it suggests passing.