Click on one of the three pieces at the top of the grid then click on a green square to place the piece in the grid. The computer will then place a piece on the grid in an available green square, and you continue to alternate until there is a winner. You play by extending the black line formed by your respective moves, absorbing adjacent unattached sections.
If one or other player has no legitimate moves left for their turn, they are declared the winner. This happens when their opponent either takes the only remaining end of the black line to the edge of the board, or joins the two ends of the black line together.
This is a computer variant of the original Black Path board game from 1960.