Domino is a tile game played with an array of pieces with matching ends. They are placed on a flat surface, usually a table, in a pattern or in a line and then one by one each domino must be struck so that its end matches with the other two adjacent ends of the domino before it. The result is a chain of dominos that develops into an intricate design, often called a snake-line. The game may be played with only a few tiles or a few thousand of them. Hundreds of dominos can be set up on stage in a domino show, where builders compete to build the most elaborate domino structure before a live audience.
The most popular types of games with dominoes are blocking and scoring games. The object of these games is to empty the opponent’s hand while blocking them from doing so. Most games require a set of 28 dominoes, though larger sets are available for those who wish to play longer chains. A domino may be named for the color of its pips or for the name of the game with which it is played.
There are many different types of domino games, and each has its own rules and objectives. Some, such as solitaire and trick-taking games, are adaptations of card games and were once popular in certain areas to circumvent religious proscriptions against playing cards. Others are based on the arithmetic properties of the domino pips and allow players to take turns arranging tiles in a specified way.
The earliest known mention of dominoes is in the Chu sz yam (Investigations on the Traditions of All Things) document dated to 1120 CE. The document describes a domino like game played by a statesman who presented it to the Chinese Emperor Hui Tsung. The game soon spread to other parts of Asia and then to Europe where it became a fad in the early 18th Century.
By the late 18th Century it was possible to purchase sets of dominoes that were specifically designed for puzzle games. These domino puzzles had a pattern printed on the side of each domino and were arranged so that adjacent sides matched. There were also domino puzzles that required a player to place the dominoes in such a way that they formed a specified total.
Dominoes are most often made from polymer materials such as Bakelite, but they can be found in a variety of natural materials. Some, such as bone and ivory, have a more traditional look. Other sets are made from dark hardwoods such as ebony and are often inlaid with contrasting black or white pips. Still others are fashioned from metals such as brass or pewter or even frosted glass.
A domino effect refers to either a literal series of physical colliding events or a metaphorical chain reaction within a system such as global finance or politics. The term is often used to emphasize a chain of causative events or relationships that begin with one event and then lead to another, much like the falling dominos of a well-designed Rube Goldberg machine.