A domino is a thumbsized rectangular block of wood or plastic, with one face bearing from one to six pips (spots resembling those on dice) and the other blank or patterned. A complete set of dominoes consists of 28 such blocks.
Dominoes are used with a variety of games, most often by arranging them in lines and angular patterns to form a structure on which the pieces can be tipped over. Each tipping causes the next piece to fall, thus resulting in a chain reaction that continues until all of the pieces have been tipped over. This phenomenon has given rise to the common phrase, the Domino Effect, referring to the way in which one small action can lead to much greater—and sometimes dramatic—consequences.
The game of dominoes can be played by two or more people, and many different rules exist for various games. Most games are won by the first player to make a play that matches the pips on the open end of another tile. The winning player is called the dominoes or the winner, and his score is added to the total score for all players in the game.
Each player makes his or her move in turn, and it is important to follow the rules of the particular game being played. When a player does not follow the rules, it is said that he or she has committed a misplay. A player who does not follow the rules of a specific game may be penalized by losing points or even being dismissed from the game.
Many different types of dominoes are available, ranging from the basic 28-piece sets that are sold in stores to more elaborate and costly handmade ones. Some sets have been made of natural materials such as bone, silver lip ocean pearl oyster shell (mother-of-pearl) or ivory with a dark hardwood such as ebony for a more attractive and durable look; others are constructed of polymer clay to give a smoother, more contemporary feel.
Before each game, a player shuffles the tiles thoroughly on a flat playing surface, mixing them with his or her hands as he or she does so. Some players alternate shuffling for each game, while others agree to have the same player shuffle for all games. It is also possible to have a dominoes dealer do the shuffling for each game.
Depending on the rules of the game, each player draws a certain number of dominoes from the stock and begins playing. Generally, the player who draws the highest double or, in some cases, the heaviest single, makes the first play. Some games also state that a tie must be broken by drawing new hands.
Some domino games require that all of the dominoes in a hand match, either by color or by number of pips, and that those matching dominoes must be placed together in the line of play. Other games are more informal, allowing each player to decide which dominoes in his or her hand are appropriate for play. These informal games can be enjoyed with children as well as adults.