Domino is a set of black and white rectangular pieces, normally twice as long as they are wide. They are stacked on end to form long lines and are then tipped over. The first domino that falls causes the next domino in line to tip over, and so on until all of them are knocked down. This simple action has given rise to many different games, and it is the origin of the phrase “the domino effect,” which means that one event can lead to a chain reaction with much greater – and sometimes unexpected – consequences.
Traditionally, dominoes are used for playing positional games where each player places a domino edge to edge against another so that the total of the number on both adjacent sides is some specific value. Each domino features a number which is called its pip count. The total of the pips on each domino is also referred to as its rank or weight. Some large domino sets feature numbers written in Arabic numerals to make the pips more easily identifiable, and some are painted to make them easier to identify when they are stacked on top of each other.
The most basic domino set consists of 28 tiles, and is known as a double-six set. The most common variant of the game is played with two players, using seven tiles each. The remaining tiles are shuffled and re-formed into a stock, or bone yard, from which each player draws a number of dominoes to begin play (two players start with 7 dominoes, three players with 5 each, and four players with 4 each). In turn each player plays a domino from their hand onto the table by positioning it so that its open end matches one of the dominoes in the stock. The first player to reach a specified number of points, often 61, wins the game.
Some domino games are based on scoring rather than positioning, and each player has a certain amount of dominoes to play with at any one time. To score, a player must place a domino so that the number on the open end of the tile matches an existing domino in the chain. When a domino is placed in this way, it is said to be “blocked,” and the player is then out of that particular turn.
A good example of this type of gameplay is the game of Draw, which is popular in many countries around the world. The rules are fairly simple: each player starts with a hand of seven dominoes, and passes their turn when they can no longer make a legal move. When a player is blocked and cannot continue the play, they must pick up all the dominoes in their opponents’ bones yards and return them to the bone yard so that they can be drawn again at their next turn. This allows the defending player to re-enter the game. In this way the game can last for hours.