Dominoes are small rectangular blocks with groups of spots or pips on one side. They are used to play a variety of games. The most popular domino games fall into four categories: bidding games, blocking games, scoring games and round games. Almost all of these games have extremely similar, or even identical, rules. The exact rules of a particular game can differ from place to place, and even within a given group of games there may be many variations on the same theme.
When a domino is played, it has the effect of “setting off” a chain reaction that causes other tiles to fall over and continue the sequence. This process is known as “dominoing.”
In the beginning of a domino sequence, each player must make sure that the tiles he has in his hand are playable. If he cannot play one, he must “knock,” or rap the table with his finger, to signal that his turn has passed and another player should begin playing. Depending on the rules of the particular game, a knock may also be done to indicate that a double must be played immediately (as the next tile in line).
As dominoes tumble down, their potential energy increases, and they can exert force on each other to keep going. The speed at which the sequence of dominoes falls is dependent on the size of the triggering domino and the distance between it and its first victim. Dominoes can also generate a pulse of energy when they are pushed together like the way a firing neuron sends an impulse down an axon.
Depending on the rules of the particular game, the value of a domino may be determined by the number of spots it has on each side or by its number of sides. A domino can be referred to as a double, a spinner or a nipper. A double with four pips on two ends is considered more valuable than one with six pips on both sides.
After a hand or game has ended, the winning players are those who have the fewest number of total pips in their remaining tiles. When the losing players are tied, they must chip out or recall their last domino and the winner is the player who has the least total number of pips on his tiles left. If the scores are equal, the winners may choose to count only one end of a double instead of both ends.
Most domino sets are made from polymer materials, but some are carved and decorated in traditional styles from woods such as ebony or mahogany. Others are made from natural materials such as bone, silver lip ocean pearl oyster shell (mother of pearl), ivory or a dark hardwood such as ebony; and still others are fashioned from metals such as brass or pewter.
When Lily Hevesh prepares her domino installations, she begins with a test version that allows her to correct problems before she puts it all together. Then she adds 3-D sections, flat arrangements and lines of dominoes that connect the entire installation. She tests each section in slow motion to ensure it works correctly before she adds the real thing. Even though she’s pretty good at preventing big accidental topples, they do happen sometimes. Hevesh makes sure to omit a few of the smaller pieces until the very end, so she doesn’t have to start over from scratch if an accidental bump occurs.