A domino is a thumb-sized rectangular block with one face bearing an arrangement of dots (or pips) and the other blank. The number of pips indicates its value, which ranges from six to none or blank.
Almost all games of domino involve some form of scoring. To score, players must count the pips on the tiles left in their hands after a hand or game ends.
Rules
Many different domino games exist and each has its own rules. Some are incredibly complex while others are quite simple. The rules of a game depend on the number of players, whether a spinner is used and how points are scored. Some games go by the same name in various parts of the world but have very different rules. The best book available on the subject is The Great Book of Domino Games.
To begin play, the players shuffle a basic set of 28 dominoes (up to double sixes) and form the boneyard. Each player draws seven dominoes from the stock, turning them over to look at them without revealing their value. The first player then puts down a domino in the middle of the table.
On each turn, a domino must be played so that at least one of its pips matches an adjacent number on a previously played tile. The open ends are counted, and a player scores when this total is exactly divisible by five or three.
Materials
Over the centuries, dominoes have been made from a wide variety of materials. Modern domino sets are usually made of synthetic materials such as ABS and polystyrene plastics, Bakelite and other phenolic resins. These are lightweight and relatively inexpensive compared to other materials such as ivory or wood. Modern domino sets also often use a different color for the dots of each different value to make it easier to identify them and distinguish between one-spots from two-spots, etc.
In the past, dominoes were sometimes made of natural materials such as bone, silver lip ocean pearl oyster shell (mother of pearl), or ivory with a dark hardwood such as ebony for the lower half. Many sets of this type still exist today.
Some people have even crafted their own sets using stone, such as black marble or vibrant agate. This can be a very elegant and luxurious look to a set of dominoes, although they can also be heavy and unwieldy for some players.
Variations
Most domino games are blocking games, where the objective is to empty your hand while blocking your opponent’s. There are also scoring games, which involve adding a number to a running total. Finally, there are trick and trump games, which draw inspiration from card games.
Dominoes are normally twice as long as they are wide, and have a line in the middle to divide them visually into two squares. The ends of each domino are numbered from one to six, with doubles having an additional endpoint that acts as a spinner.
Most game rules differ from one variant to the next, but in general each player draws a certain number of dominoes for their hand, adds them to the tiles they are holding and then plays them according to the game’s rules. If a player draws more for their hand than they are allowed to, they may be required to bye the extra tiles back into the stock.
Scoring
Depending on the game-type, players either score based on the number of dots in their opponents’ hands or a total point limit is set. When the total point count is reached, the player with a higher score wins. If no one can make a play, the game ends as a draw and each player counts the dots in their own hand.
If a domino has two or more unoccupied scoring ends, the value of those numbers is added together to form the score. A blank tile counts zero points. Doubles belonging to the same suit count for their combined value.
For example, a 3-6 domino adds 15 points to the board count. A single-end domino is considered a spinner if it can be played on all sides. Other scoring systems use a combination of the above systems, or assign different values to the various pips on a domino. For example, a double eight may be worth four points, while a five is worth three.