Domino is a game of skill, strategy, and chance that began in ancient China and has developed into many different variations. It is played with small rectangular blocks that are marked with groups of dots, called pips, on each face. A complete set of dominoes has 28 such pieces, and they are usually arranged in lines or angular patterns.
Each player draws a certain number of tiles for their hand, depending on the rules of the game being played. These tiles are then placed in front of the player. The pips on each domino can be used to make matches and build structures, but they are also the key element in scoring games. The number of matching pips on a domino that has already been played is known as its count.
Throughout history, domino has been made from a variety of natural and man-made materials. The most common is plastic, but sets are also available in wood (ebony, walnut, and other hardwoods), bone, silver lip ocean pearl oyster shell, ivory, or even ceramic clay. The most sophisticated domino sets are made of high-quality, hand-crafted materials and have a richer feel and appearance than those made of polymer.
Once a player has played a tile, it becomes part of the line of play and the open end is considered the starting point for counting. The players then play their dominoes into the line of play, either lengthwise or crosswise. Doubles are always played across the line of play, while singles are played lengthwise unless otherwise specified.
A rule variation that may be employed during a game is known as the “highest double” rule. This allows the player who holds the highest double to start playing first. In the event that no player has a double to begin with, the player who has the heaviest single begins. If a player plays a tile that does not match with any other tiles, then that player must draw new hands until he or she finds a match. This is known as a misplay.
In addition to using the pips on a domino to make matches and build structures, the physics of the game also offers lessons about energy. Physicist Stephen Morris explains that standing a domino upright gives it potential energy, which is stored in the fact that it is standing up against gravity. When the domino is subsequently knocked over, much of this potential energy is converted to kinetic energy, which causes one domino after another to fall.
When you next play a game of domino, try to pay close attention to the way your dominoes fall as they tumble toward each other. Make a conscious effort to flick the first domino only gently, and note how each subsequent domino seems to fly up a little farther than its predecessor. As you continue to do this, you’ll be able to see how the power of gravity works to create this chain reaction.