Dominoes are rectangular blocks of clay or similar material, typically double-sided with a pattern of dots. These are called “pips” and may range in size from six to none. They are placed on a flat surface and, in turn, a sequence of other dominoes is triggered to fall over them. The resulting chain of toppled dominoes is sometimes called a “domino line,” “domino train” or simply “domino.” In addition to the many games that can be played with these, they are often used as decorative objects in artistic works, and for making curved lines, grids that form pictures when they fall, stacked walls and 3-D structures such as towers and pyramids.
The rules of a domino game vary widely and are sometimes confusing. However, nearly all of these games fit into four categories: bidding games, blocking games, scoring games and round games.
To play a domino, each player draws the number of tiles permitted by the rules of the particular game and places them in front of him. He then takes his turn by placing a tile on the table, positioning it so that its matching end touches one or more ends of another domino already laid down on the table. This tile is then matched to the other dominoes on the table and may be moved around to new positions.
Each domino has two matching sides that show numbers, but the blank or unnumbered side is also used. The value of a domino is determined by the number of pips on its two matching sides. Those values may be added together to form a total value, known as the rank or weight of a domino, which may be used in scoring.
A domino has a line in the center that divides it visually into two squares, each marked with an arrangement of pips like those on a die. The pips on each end of the domino are arranged differently; the sum of these is the value of the domino. The other side of the domino is blank or unmarked, and the value of this side can be ascribed by a player to whatever suit he wishes.
After a player has played a domino, it may be played to another tile and so on until the whole of the domino line is completed. Then the player who has the highest number of pips on the line begins to score.
Each time a domino is played, it forms an all-or-nothing pulse that travels down the line as quickly as a nerve impulse in your body, and just as unstoppably. This is why the domino effect is so powerful. Once it is triggered, the line will continue to grow and expand until an error in judgment or an act of bad luck stops it from continuing. This is why domino players are so careful not to make mistakes. If a mistake is made, the offending tile must be recalled before the next player plays.