A domino is a flat, rectangular tile marked with pips or spots. Typically, it is divided into two square ends, but there are also some extended sets that feature more than one pip on each end.

When playing a domino game, each player in turn places a tile edge to edge against another. The pips on the faces of these pieces can represent any number, from zero to six, depending on the game. Some games also use the pips to represent a specified total. In Chinese dominoes, the pips are blank and may not even be visible at all, but in European dominoes they are clearly labeled.

The origins of dominoes are unclear, though they have been mentioned as early as the 10th century. Western dominoes, however, have a long tradition in Europe, where they were first recorded in Italy and France, probably brought to England by French prisoners-of-war during the 18th century.

Traditionally, a European domino set includes 28 tiles, or bones, pieces, men, stones, cards or just dominoes. A single set of 28 tiles contains all combinations of spot counts between zero and six. In other types of domino games, more than 28 tiles are required.

In addition, most European domino sets have the same tile layout, a straight line dividing each face into two square ends. These end tiles are numbered from zero to six, with some variants such as Five-Up using multicolored tiles or Hector’s Rules having seven pips on each end and allowing players to play double tiles on their opponents’ hands.

Dominoes are commonly played for entertainment, especially in bars and cafes. A traditional European domino set consists of 28 tiles, which are either marked with pips or blank on their backs.

Many people enjoy toppling dominoes by flicking them and watching them fall in a line, like the chain reaction that occurs when a car hits a highway or a rocket launches. Physicist Stephen Morris, who studies the effect of gravity on dominoes, says that when you stand a domino upright, it stores potential energy. Then when the domino falls, much of that potential energy is converted into kinetic energy, which can be used to knock down the next domino in the line.

The domino effect is a natural phenomenon that can occur in a variety of settings. It can be observed in games such as Rube Goldberg machines, and it can also be exploited to create complex systems.

When applied to fiction, it can help writers answer the question “what happens next?” in a compelling way. For example, in the novel The Art of Fielding, the main character’s life is influenced by the domino effect as he makes his way to and through college.

In a similar way, a domino effect can be applied to personal relationships and career success. It can be used to determine what tasks are most important, which ones receive the most focus, and which will pay off in the future. It can also be used to figure out how to prioritize a long list of projects and activities so that you’re not wasting time on low-impact or low-payoff tasks.