Domino is a generic term that describes a game played with flat, thumbsized blocks called dominoes (also known as bones, cards, men, pieces or tiles). A domino has two square ends bearing from one to six dots or pips; it is normally twice as long as it is wide. The pips may be either white, black or blank, and each end is numbered with a value of 1, 2, 3, 4, 5, 6, or 0. The number of pips on a domino determines its rank or weight; a double has six pips and is thus heavier than a single.
There are numerous games that can be played with a domino set, some of which share the same name but have different rules; others have very similar and sometimes identical names but very different rules. Typically, the dominoes are arranged in a large circle and each player draws a tile from the stock to make his first play of the game. The player who draws the heaviest domino is the first to make his move, or begins play. He may also be referred to as the setter, downer, or lead.
Some people prefer to use a dice or coin to determine who makes the first move. There are also a variety of other methods for determining who will make the first play, including drawing lots and letting the winner of the last game open the next. The order of play can also be determined by seating arrangement, or the players can agree to rotate counter-clockwise after each round.
Unlike the familiar plastic domino sets, many European-style dominoes are made of bone, silver lip ocean pearl oyster shell (mother of pearl), ivory or dark hardwood such as ebony and have contrasting black or white pips inlaid or painted on the faces. These sets have a more unique look and are often heavier in weight than polymer dominoes.
The word domino derives from an Italian word meaning “flip,” a verb that is used to flip a coin or to arrange the ends of two pieces of wood in the shape of a triangle, so they can rest against each other. The earliest uses of the word were to denote a long hooded cloak that was worn over a mask during carnival season or at a masquerade, and later, it came to mean a game involving throwing a coin or dice.
While the most common domino sets contain only double-six dominoes, they can be “extended” by introducing more specialized ends that add additional values. The most commonly available extensions are double-nine, double-12 and double-18 dominoes. Larger sets that have more than six pips on each end are possible, but are very rare and rarely seen in use. Having too many pips on an end can also be problematic, as it increases the amount of time required to read the values, making a domino harder to maneuver and play. This problem is minimized by using larger, more readable Arabic numerals for the pips on some large domino sets.