A domino is a small rectangular block with blank or marked surfaces resembling those on dice. A set of these small blocks is the basic unit for playing many games. The word “domino” can also be used as a noun to mean any action that cascades, such as the way a series of dominoes fall after one is tipped ever so slightly. In writing, a domino effect refers to any action that causes the next one to follow suit, for example the way a character’s actions in a novel might affect other characters.
Dominos can be made from various materials, including wood, bone, ivory, marble and resin. They are usually colored with paint or inlaid with contrasting colors (e.g., white or black). The open ends of a domino are typically labeled with pips. A traditional domino set is usually made from bone, silver lip ocean pearl oyster shell or ivory with a dark hardwood, such as ebony, with contrasting pips (inlaid or painted). A domino is usually about a half-inch tall and wide, but may be larger or smaller.
When players make a play, they place the tile on the table, face up. The pips on the tile must match those on adjacent dominoes to create a line of play that extends outward from the player’s hand. This configuration of dominoes is sometimes called a layout, string or line of play. Most domino games require a line of play to be completed, but some can be played with just one or two dominoes.
If a domino is not matched correctly, it must be recalled. The player may then draw a new domino for his hand, or “bye” and take another tile from the stock, depending on the rules of the game. If no more plays are possible, the game ends.
After each player draws his hand, he places it on the table in front of him. The player holding the heaviest double (based on total number of dots) starts play. If no player holds a double, the player with the highest single begins.
If a player draws more tiles for his hand than he is permitted, they are known as overdraws and must be reshuffled before the next player draws. The player to the right of the overdrawn hand takes the extra dominoes without looking at them, and passes them to his teammate (or, in a team game, to his opponents). If an overdraw is discovered after the other players have drawn their hands, it must be reshuffled before the other players draw their next hands. In some games, the extra dominoes remain face down and may be “bought” (See Passing and Byeing) later in the game.