Domino is a game played with a set of small, rectangular blocks called dominoes. These are usually made of wood or plastic and have a number of dots on each end that resemble the spots on a die. The most common dominoes are double-sided, with one type of pips on each side. A domino is considered to be a single domino when the pips on both sides match; otherwise, it is a double. The pips on each face are often grouped into suits, such as the threes, fives, and nines. The name of the suit is determined by the total number of pips on the dominoes’ ends.
Throughout history, different materials have been used to make dominoes, including bone and ivory; dark hardwoods such as ebony; frosted glass and ceramic clay; metals; and modern polymer. In recent years, many domino sets are made of a high-density polymer such as PVC or acrylonitrile butadiene styrene (ABS), which has the advantage that it is durable and dishwasher safe.
There are a wide variety of domino games, most involving scoring or blocking opponents’ play. For example, players can use a domino set to play concentration or to duplicate card games that were once popular in some regions as a way to circumvent religious prohibitions against playing cards. The most common blocking game is the game of slapjack, which involves laying tiles down in such a way that when each player has two matching tiles left in his or her hand, those tiles are knocked over. The game of piquet is another blocking game that uses dominoes.
In addition to blocking and scoring games, dominoes are also used as building blocks for complex mechanical devices such as Rube Goldberg machines. They are also used in electronic circuitry as amplifiers and digital signal processing components.
When dominoes are arranged so that the arrows on their edges point in a particular direction, they can form patterns that create images or words. This is known as domino art. Typical designs include straight lines, curved lines, grids that form pictures when they fall, and 3D structures like towers or pyramids.
The term domino is also used to refer to a person who takes on leadership roles in organizations. Leaders are usually selected based on their ability to stand out and motivate others. They are also able to build consensus and lead teams to accomplish goals. Leadership is not the same as management, however. Managers tend to take a more bureaucratic approach and are less prone to standing out in the crowd.
While a domino is most commonly referred to as an object used in a game, it is actually a mathematical term that refers to a set of numbers. It is a special case of the Fibonacci sequence, which describes the numbers that occur in a repeating pattern in nature such as the spiral of a sunflower or the stairways of a staircase. The word is derived from the Latin domini, meaning “he who leads.” The concept of domino theory in mathematics was developed by Italian philosopher Giuseppe Peano.