# What is Domino?

Domino is a game where the objective is to set up and arrange a series of numbered tiles so that they all come to rest in one row or another. This is done by placing the numbered tiles on a flat surface, such as a table. The tiles are marked with a number or symbol on each end, known as pips. These pips distinguish the individual dominoes from dice or playing cards.

The word domino is also used to describe the sequence of events that occurs when a person or thing experiences a setback or problem and, in turn, causes other events to occur. For example, when a woman gets pulled over for driving too fast, the incident may have a domino effect, where other drivers may speed up and cause additional traffic problems. The term is also commonly used to refer to a chain reaction that can occur in an organization or community, such as when a company merges with or acquires another.

Like the playing cards of which they are a form, dominoes are rectangular in shape and have a line down the center that divides each end into two squares. The identity-bearing face of each tile is blank or identically patterned on both sides. Each square is marked with an arrangement of dots, called pips, that distinguishes the individual dominoes from each other. Dominoes are similar to dice in that they can be arranged in various ways to play many games.

Typically, the number of pips on each domino determines what type of game is played. A domino with six pips on each end is considered the most valuable in most sets. More common are dominoes with two, three, five or four pips on each end. Some domino sets, called extended, contain a larger number of unique ends and can be used to play more complex domino games.

In most games, a domino must be laid down before any other pieces can be placed on the table. A player who cannot lay a domino must “knock” the table, or verbally signal that they can’t proceed with the current hand. After knocking, play passes to the next player.

Some domino games involve blocking opponents’ plays, while others are scoring games that count the total value of a domino’s pips. The most popular domino games include tic-tac-toe, draw poker, domino wars and Mexican train. In addition, some domino games are adaptations of card games that were popular in certain areas to circumvent religious prohibitions against playing cards.

Dominoes can be made from a wide variety of materials, including metals (such as brass or pewter); woods such as bone or ebony; stone (such as marble, granite or soapstone) and ceramic clay. In recent years, however, the popularity of polymer dominoes has increased. These are often less expensive than wooden or metal sets and are more durable. Some people also make their own sets of dominoes using materials such as cardboard or paper.