Domino (plural: dominoes) is a small rectangular block of wood or plastic, normally twice as long as it is wide. Its surface is marked with a series of dots, similar to those on dice, called spots or pips. The value of a domino is determined by the number and location of its pips, which are usually arranged in pairs on either side of the square. A domino may have one, two, three, or four pips, with each pair being of equal value. A domino is most commonly used in a game of chance or strategy, and it can be stacked vertically or horizontally.
The term domino is also used to refer to the act of placing a domino into a position to be acted upon, or to a series of events or conditions that lead to such an action. In fiction, the concept of a domino effect is often employed to describe the way that one event can affect another, and then influence others still further, like a line of dominoes falling with the simple nudge of a single finger.
A domino is normally played on a flat surface, such as a table or floor. The player begins by arranging his or her dominoes into a stack. Then, he or she chooses a domino to play. Depending on the game being played, a domino may be used to replace other dominoes that have already been played or to fill in empty spaces between rows of stacked dominoes.
Most domino games involve blocking the opponent or scoring points. Some, such as bergen and muggins, score by counting the number of pips in a player’s losing hand. The term domino also applies to a number of solitaire and trick-taking games that duplicate card games but can be played without cards, allowing people to play them even where religious prohibitions forbid the use of such devices.
While a domino is most often used for games, it can also be used to teach children about numbers and sequencing. Many children enjoy lining them up in rows and watching them fall with the nudge of just one. In addition, many people like to watch domino shows, where builders set up hundreds or thousands of pieces in careful sequence, and then see them all fall with a single blow.
In the past, domino sets were made from natural materials such as bone, silver lip ocean pearl oyster shell (mother of pearl), ivory, or dark hardwoods such as ebony. These types of dominoes were typically more expensive than polymer domino sets. Recently, however, more affordable domino sets have been produced from polymers such as melamine. These dominoes are generally less glossy and more durable than their natural counterparts. Some manufacturers produce sets from exotic and semi-precious stones such as marble, granite, or soapstone. These have a more refined look than polymer sets, but are still less expensive than traditional wooden or marble and brass sets. They are also available in a variety of colors, such as black, white, or red.