How Dominoes Are Played

A small rectangular wood or plastic block, the face of which is divided, usually by a line or ridge, into two squares marked with an arrangement of dots or symbols resembling those on dice. Dominoes are typically twice as long as they are wide, making them easy to stack on top of one another and remove when not in use. A domino has a number of value marks on its either end (also called ends), which indicate the rank or weight of the tile and the total value of a domino chain (a sequence of tiles played to each other). Dominoes are also sometimes referred to as bones, cards, men, pieces, or tiles.

Dominoes can be used to play a variety of games, but most fall into four categories: bidding, blocking, and scoring. During the course of a game, a player must place one of his or her tiles so that its open end matches with an adjacent open end of an already-played domino. A matching pair of open ends forms a domino chain that continues to grow on the table as more tiles are added. This line of play, referred to as the layout, string, or line of play, is an important aspect of domino games and must be maintained for the success of the players.

When a domino is played, it must be positioned so that its ends touch fully and its value is completely visible. A double may be placed in any of three directions – cross-ways across a domino that is perpendicular to it, or in a diagonal direction from the left or right of a domino that is parallel to it.

The order in which a domino is played is determined by the rules of a particular game. Some rules specify that the first play must be made by a player holding a higher-value domino, while others require the highest double in a hand to make the first play. The amount of score a player receives is generally determined by counting the number of pips on the dominoes that remain in the losing players’ hands at the end of a hand or the entire game, although some rule variations allow for different methods of scoring.

Many domino sets are “extended,” meaning that more than 28 tiles are included. The most common extended domino sets include double-nine, double-12, and double-15. The addition of more pips increases the number of unique combinations of ends and thus the number of possible tiles that can be formed.

When playing domino, a player must be careful not to place his or her tile so that it overlaps an existing piece, as this is known as a misplay and can result in the loss of points. If a misplay is not discovered before the next player plays, the overlapping piece must be removed from the layout. In addition, if a domino is placed on the wrong side of a previous play, that must be corrected before the next player begins to play.