When dominoes are laying flat, they have a small amount of gravitational potential energy. But as soon as the first one falls, that energy is converted into kinetic energy—the force of movement—which travels to each domino until they all fall.
When it is your turn, move a domino so that at least one of its numbers matches an adjacent number on a neighboring domino. You then collect the domino you moved and any other matching dominoes.
Rules
There are a variety of domino games with different rules. However, they all have the same objective: to get more points than your opponents. The first player to do so wins the game.
Each player has a hand of dominoes that they can play. The winner of a hand scores based on the number of dominoes they have left in their opponent’s hands (not including the last double, which is worth one point).
The basic rules for scoring are that each open end of a domino may only be played on once, and that it must be joined to another domino with an open end of the same value or a pips-only end. Exceptions can be made for a line of pips, or for a knight, bishop, and rook, which can only connect diagonally. Players can also buy tiles from the stock if they have enough points to do so. If a player cannot buy any tiles, they must pass and the next player takes their turn.
Variations
A domino is a tile that has identifying marks on one side and is blank or identically patterned on the other. The identifying marks are called “pips.” Dominoes can be arranged to form lines that are connected, creating many different game variants.
One variant is based on scoring. Players count the number of pips on each exposed end of a double that has been played to determine their score. If the total is a multiple of five, the player scores five points.
Another variation is based on blocking. Players start by drawing seven dominoes from a boneyard and placing them on the table. Players then bid to be the first to play a domino on a given turn. The player with the lowest bid wins. Those who cannot play must draw from the boneyard until they can. This gives the game a poker-like feel. The game also features a “spinner” (a double that can be played on all four sides) that creates a branching line of play.
Materials
Like a playing card or a dice, each domino is marked with an arrangement of spots, called pips, to identify it. One side of the domino has the pips, while the other is blank or identically patterned (the absence of a single pips indicates zero).
Historically, European dominoes were made from animal bone, especially ox bone; and later, ivory for wealthier players. The pips were usually painted black or white.
In the early 20th century, a manmade plastic called Bakelite was invented. The material was formed by condensing phenols and formaldehyde into a hard resiliant substance. This was used to make a wide variety of products including dominoes, which were sometimes marked with a logo. Since that time, dominoes have been manufactured from a huge range of materials.
Scoring
Dominoes are a type of flat, thumb-sized block with either blank or numbered ends. They are usually twice as long as they are wide. A complete set has 28 pieces. The numbered ends are called spots or pips. Each spot is worth one point in most games.
The player with the highest number of pips in his or her hand is declared the winner. This player earns additional points based on the value of his or her opponents’ hands. The total is computed by adding the number of pips in each opponent’s hand to the winning player’s pip count.
Depending on the game-type or setting, rounds may be predetermined or played until a specified point limit is reached. Often the winner is determined after all rounds are completed. The winner is then awarded a trophy or similar prize. Alternatively, players may choose to draw lots or begin play by setting the heaviest domino. In either case, the order of play is usually clockwise.