Domino is a flat, rectangular, black game piece used in a number of games. The pieces are typically twice as long as they are wide, and they usually feature a line that divides the piece visually into two squares, called ends, each of which has a number of spots or pips.

The spots on a domino’s end vary from zero to six. The highest-value piece has six pips on each of its two ends; the lowest-value piece has fewer or none.

Traditionally, each domino’s identity-bearing face is divided into two squares by a line or ridge, each of which has an arrangement of spots or pips (called “pips”) like those found on dice. Unlike dice, the spots on a domino’s end do not always have to be arranged in order. Some dominoes, especially in China, are blank on one or both sides and may be used for any number of different games.

Most traditional domino sets have one unique piece for every possible combination of two ends with zero to six spots. A double-six set, which is the most common set, has 28 unique pieces; however, sets of progressively larger lengths are also known.

Many larger domino sets include additional pips on each of their ends to increase the number of unique combinations. These are often referred to as “extended” sets.

Some extended domino sets have as many as eight ends with pips. These can be used in a variety of different games, including block-and-draw, which involves a single player drawing seven tiles at random from a stock of 28 shuffled dominoes.

Other extended domino sets have as many as nine ends with pips, and these can be used in games that involve more than four players. The most common extended set is double-nine (55 tiles), and there are also double-12 (91), double-15 (136), and double-18 (190) sets.

A domino effect is a cumulative effect that occurs when one event sets off a chain of similar events. This can be a physical or psychological process, and it may have a significant impact on the outcome of a situation.

In a business setting, the domino effect is often referred to as the “chain reaction.” It is a powerful tool that can be used to motivate people and increase sales. It is also useful in personal relationships, as it can inspire people to take action when they see the effects of their actions on others.

The domino effect can be a valuable tool for marketers, as it can help them create a recognizable image and brand. It can also inspire customers to purchase more products, which can improve a business’s bottom line.

Despite the domino effect’s effectiveness, it can also be dangerous. It can be triggered by a small change in a person’s behavior, which then activates a domino effect on a large number of other related behaviors.

For example, a person might begin to exercise more regularly and then increase their intake of fresh fruit. This can have a domino effect on their diet, which in turn affects their weight. Or they might begin to cut back on their sedentary activities and spend more time outside of work, which has a domino effect on their overall health.