Domino (also known as bones, cards, men, tiles, spinners, or tickets) is a flat thumb-sized rectangular block of wood or other material that is blank on one side and patterned with an arrangement of dots, called spots or pips, on the other. A domino set normally consists of 28 pieces. Each domino has a value, indicated by an arrangement of dots on its face, that varies according to the game being played. The sum of the values on both sides of a tile indicates its rank or “weight” – a heavier domino has more spots than a lighter one.
Most domino games involve arranging and playing tiles to build lines of enclosed spaces or “cells” on the table. A player may earn points for each cell he creates, for matching the value of his domino to that of the first domino played, or for scoring combinations of cells – for example, two adjacent cells in a row or four overlapping cells on the edge of the board. The number of points earned for a winning combination will vary depending on the game and the rules agreed upon by the players.
The most popular domino games are those based on matching the ends of one or more dominoes together. When a domino has the same value on both ends, it is known as a double. Usually, only the long end of a double can be used to connect additional tiles to it; however, some games allow new tiles to be placed on all three open sides of a double – known as a spinner – and these are sometimes considered to be “heavier.”
Once the players have drawn their hands, a player whose hand is determined by drawing lots or by who holds the highest domino (depending on the game) places the first tile onto the table. Generally, the player to his left makes the next play. This player is referred to as the setter, downer, or leader.
Some players prefer to use different rule variations for the same game, including variants on how to count the pips of the opposing player’s tiles, or how to score the game. These rule variations must be agreed upon by the players before the game begins.
In some games, a player who cannot make a play may pass his turn to the opponent by knocking over all of his own tiles before the opponent does so. This is also known as “buying” tiles from the stock. There are also some games that require all players to buy their own tiles. Typically, the number of purchased tiles is not limited, but players should be aware that buying more than required can decrease a player’s total score.