Domino (also dominoes) is a game in which players take turns placing a domino, or a set of dominoes, on the table. Each domino is divided, by a line or ridge, visually into two squares, each bearing from one to six pips or dots. A domino may be blank or numbered, but when it is numbered it must have a unique number showing on both ends. A domino with matching numbers on both ends is said to be a “double”; dominoes of this type are used to form chains of tiles which are then “laid” (or deposited) on the table.
Dominoes are normally twice as long as they are wide, and this makes them easier to stack after use. Most domino sets contain 28 pieces, although larger ones are possible. Some sets also include “extendables” which may increase the total number of pieces in the set by adding more rows and columns to the original structure.
The most common domino games involve blocking or scoring by building lines and angular patterns of tiles. Other games are adaptations of card games, such as solitaire or trick-taking. Some games require the players to match or match and lay all of their own dominoes before their opponents can do so, while others have rules for winning by achieving particular combinations of matches and laid dominoes. The earliest known dominoes were of an Italian and French design, but the modern version has been standardized since the early 19th century.
When someone is described as having a domino effect, it means that they cause a chain reaction of events which are not only significant but that have the potential to affect many other things, often without warning. A person might, for example, have a domino effect in the workplace by encouraging other employees to take steps that are detrimental to the company.
A domino effect can also be a metaphor for something that happens in a story or an article. For instance, a writer might have a scene domino which isn’t really needed in the story, but it provides a visual image for what the author is trying to say.
As a rule, the first player to lay a domino begins the game by placing an opening double. This is determined by drawing of lots or by who has the heaviest hand. If no player has an opening double, the highest value domino in any of the players’ hands is played.
Each player must, in turn, play a tile onto the table and position it so that its end touches one of the existing ends of the domino chain. Each time a new domino is played, it must touch the end of the next domino in the chain, and so on, until all the players have finished playing their tiles or have run out of them. If a player cannot lay a domino in his or her turn, that player is said to have “chosen” not to play and play passes to the next player.