The game is played with a set of 28 tiles. Each of the tiles has two sides, each of the sides is marked with 0 to 6 pips, for example 0-0 (a completely blank tile), 1-0, 1-1, 2-0, and so on.
A tile which has the same number on both sides is called a "double." All combinations of numbers on the tiles are unique so that no two tiles are the same. When the game begins, each player will be dealt 7 tiles.
The player who holds the highest double, or the highest rank of tiles if neither player is holding a double, will start the game. The two players will take turns to place a tile onto the table.
During your turn, you can choose a tile in your hand which has a matching number of pips on one side with that of a tile on either end of the domino chain, then click and drag the tile to that end. For example if the tile on one end of the domino chain is a 5-4, you can choose the 4-3 in your hand and connect it with the 5-4.
Note that when a tile is placed, it must be in a vertical or horizontal position that the matching sides of the two tiles are adjacent.
A double must be placed perpendicularly to the previous tile, while the next tile played to a double must also be perpendicular to the double.
Note that you can no longer connect a tile to an end of the domino chain when it is blocked by other tiles or when it reaches the edge of the table.
If you have run out of moves, you can draw a tile from the stock pile, but you cannot do so if the stock decreases to 2 or below, and in this case, you will need to pass the turn to your opponent.
The round continues until a player empties his hand and wins the round, then the total number of pips on the other player's remaining tiles will be added to the winning player's score.
If both players still have tiles in their hands but neither of them can make a move, the round will also end.
In this case, the player who has a smaller number of pips on the tiles in his hand wins, and the difference in the two players' numbers of pips will be