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Domino is a board game played with rectangular tiles marked on one side with groups of spots called pips. The most common domino sets contain 28 or 55 tiles, and large sets can be used for games with several players.
The game of domino originated in Europe, where it quickly spread to Austria, southern Germany and France. Its popularity grew in the mid-18th century, and it soon came to England.
It is also popular in Asia and Africa, where it has been in use for more than a thousand years. It has been played by people of many different cultures, and is a popular form of recreation.
There are a number of different types of domino games and variations, some of which are quite sophisticated. A few of the most common are blocking and scoring games. Other games are more like puzzles or trick-taking, where the players must find out the secret number on a tile and then play it onto a domino chain, which gradually increases in length.
In blocking and scoring games, the player who gets a specific number first wins. Then the next player plays a tile with that same number and so on until all the numbers have been revealed, or until the players have run out of dominoes.
Some types of dominoes have identifying marks on their faces, while others are blank. These distinctions are sometimes confusing for beginners.
Each domino has a line down its middle that divides the two ends into squares. The number of pips or spots on each end determines the value of that domino. The heaviest domino has six pips on each end, and the lightest has none or only a few.
The number of pips on a domino’s face can be anywhere from six to zero, or “blank” (the number is always shown on the other end). The heaviest domino is called a “double-six,” while a double-blank is the lightest.
A domino’s face is divided into two squares by a line, which can be either straight or curved. The tiles are usually twice as long as they are wide, making it easier to re-stack them after playing.
Once a domino has been knocked over, much of its potential energy converts to kinetic energy, the energy of motion. This energy can then be transmitted to the next domino in the chain, causing it to fall as well.
In 1983, a professor of physics at the University of British Columbia named Lorne Whitehead published an article in the American Journal of Physics that illustrated this process using dominos. He showed that a domino that was half the size of another domino could knock over the other, setting off a chain reaction that would send both dominoes falling.
Similarly, when a domino is set up in a circle, it can take several nail-biting minutes for the tumbling pieces to reach each other. That’s because gravity is a big part of the domino-falling process.
