Dominoes
Overview

Dominoes generally refers to the collective gaming pieces making up a domino set (sometimes called a deck or pack) or to the subcategory of tile games played with domino pieces. In the area of mathematical tilings
Tessellation
A tessellation or tiling of the plane is a pattern of plane figures that fills the plane with no overlaps and no gaps. One may also speak of tessellations of parts of the plane or of other surfaces. Generalizations to higher dimensions are also possible. Tessellations frequently appeared in the art...

and polyomino
Polyomino
A polyomino is a plane geometric figure formed by joining one or more equal squares edge to edge. It is a polyform whose cells are squares. It may be regarded as a finite subset of the regular square tiling with a connected interior....

es, the word domino often refers to any rectangle
Rectangle
In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle...

formed from joining two congruent squares edge to edge. The traditional Sino-European domino set consists of 120 dominoes, colloquially nicknamed bones, cards, tiles, tickets, stones, or spinners.
Encyclopedia
Dominoes generally refers to the collective gaming pieces making up a domino set (sometimes called a deck or pack) or to the subcategory of tile games played with domino pieces. In the area of mathematical tilings
Tessellation
A tessellation or tiling of the plane is a pattern of plane figures that fills the plane with no overlaps and no gaps. One may also speak of tessellations of parts of the plane or of other surfaces. Generalizations to higher dimensions are also possible. Tessellations frequently appeared in the art...

and polyomino
Polyomino
A polyomino is a plane geometric figure formed by joining one or more equal squares edge to edge. It is a polyform whose cells are squares. It may be regarded as a finite subset of the regular square tiling with a connected interior....

es, the word domino often refers to any rectangle
Rectangle
In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle...

formed from joining two congruent squares edge to edge. The traditional Sino-European domino set consists of 120 dominoes, colloquially nicknamed bones, cards, tiles, tickets, stones, or spinners. Each domino is a rectangular tile with a line dividing its face into two square ends. Each end is marked with a number of spots (also called pips
Pips
Pips are small but easily countable items. The term is used to describe the dots on dominoes, dice, denote suits, and is the name for the small seeds of some fruits. It could be used as a synonym for dot in most situations, for example morse code....

) or is blank. The backs of the dominoes in a set are indistinguishable, either blank or having some common design. A domino set is a generic gaming device, similar to playing cards or dice
Dice
A die is a small throwable object with multiple resting positions, used for generating random numbers...

, in that a variety of games can be played with a set.

## Construction and composition of domino sets

Ivory
Ivory is a term for dentine, which constitutes the bulk of the teeth and tusks of animals, when used as a material for art or manufacturing. Ivory has been important since ancient times for making a range of items, from ivory carvings to false teeth, fans, dominoes, joint tubes, piano keys and...

/bone, or a dark hardwood such as ebony
Ebony
Ebony is a dense black wood, most commonly yielded by several species in the genus Diospyros, but ebony may also refer to other heavy, black woods from unrelated species. Ebony is dense enough to sink in water. Its fine texture, and very smooth finish when polished, make it valuable as an...

, with contrasting black or white pips (inlaid
Inlay
Inlay is a decorative technique of inserting pieces of contrasting, often coloured materials into depressions in a base object to form patterns or pictures that normally are flush with the matrix. In a wood matrix, inlays commonly use wood veneers, but other materials like shells, mother-of-pearl,...

or paint
Paint
Paint is any liquid, liquefiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. One may also consider the digital mimicry thereof...

ed). Alternatively, domino sets have been made from many different natural materials: stone (e.g., marble
Marble
Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...

, granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

or soapstone
Soapstone
Soapstone is a metamorphic rock, a talc-schist. It is largely composed of the mineral talc and is thus rich in magnesium. It is produced by dynamothermal metamorphism and metasomatism, which occurs in the areas where tectonic plates are subducted, changing rocks by heat and pressure, with influx...

); other hardwoods (e.g., ash
Ash tree
Fraxinus is a genus flowering plants in the olive and lilac family, Oleaceae. It contains 45-65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The tree's common English name, ash, goes back to the Old English æsc, while the generic name...

, oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...

, redwood and cedar); metals (e.g., brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...

or pewter
Pewter
Pewter is a malleable metal alloy, traditionally 85–99% tin, with the remainder consisting of copper, antimony, bismuth and lead. Copper and antimony act as hardeners while lead is common in the lower grades of pewter, which have a bluish tint. It has a low melting point, around 170–230 °C ,...

); ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

clay, or even frosted glass
Frosted glass
Frosted glass is produced by the sandblasting or acid etching of clear sheet glass. It has the effect of rendering the glass translucent by scattering of light during transmission, thus blurring images while still transmitting light.Applications:...

or crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

. These sets have a more novel look, and the often heavier weight makes them feel more substantial, but such materials and the resulting products are usually much more expensive than polymer materials.

Modern commercial domino sets are usually made of synthetic materials, such as ABS or polystyrene
Polystyrene
Polystyrene ) also known as Thermocole, abbreviated following ISO Standard PS, is an aromatic polymer made from the monomer styrene, a liquid hydrocarbon that is manufactured from petroleum by the chemical industry...

plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

s, or Bakelite and other phenolic resins; many sets approximate the look and feel of ivory while others use colored or even translucent plastics to achieve a more contemporary look. Modern sets also commonly use a different color for the dots of each different end value (one-spots might have black pips while two-spots might be green, three red, etc.) to facilitate finding matching ends. Occasionally, one may find a domino set made of card stock like that for playing cards. Such sets are lightweight, compact and inexpensive, but like cards are more susceptible to minor disturbances such as a sudden breeze.

The traditional set of dominoes contains one unique piece for each possible combination of two ends with zero to six spots, and is known as a double-six set because the highest-value piece has six pips on each end (the "double six"). The spots from one to six are generally arranged as they are on six-sided dice
Dice
A die is a small throwable object with multiple resting positions, used for generating random numbers...

, but because there are also blank ends having no spots there are seven possible faces, allowing 28 unique pieces in a double-six set.

However, this is a relatively small number especially when playing with more than four people, so many domino sets are "extended" by introducing ends with greater numbers of spots, which increases the number of unique combinations of ends and thus of pieces. Each progressively larger set increases the maximum number of pips on an end by three, so the common extended sets are double-nine, double-twelve, double-fifteen and double-eighteen. Larger sets such as double-twenty-one can theoretically exist but are rarely seen in retail stores, as identifying the number of pips on each domino becomes difficult, and a double-twenty-one set would have 253 pieces, far more than is normally necessary for most domino games even with eight players.

## History

The name "domino" comes from the pieces' resemblance to Venetian Carnival
Carnival of Venice
The Carnival of Venice is an annual festival, held in Venice, Italy. The Carnival starts 40 days before easter and ends on Shrove Tuesday , the day before Ash Wednesday.-History:...

masks known as domini, which were white with black spots. These masks were named because they resembled French
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

priest
Priest
A priest is a person authorized to perform the sacred rites of a religion, especially as a mediatory agent between humans and deities. They also have the authority or power to administer religious rites; in particular, rites of sacrifice to, and propitiation of, a deity or deities...

s' winter hoods, being black on the outside and white on the inside. The name ultimately derives from the Latin dominus, meaning "lord" or "master."

Many different domino sets have been used for centuries in various parts of world to play a variety of domino games. Each domino originally represented one of the 21 results of throwing two dice. One half of each domino is set with the pips from one die and the other half contains the pips from the second die. Chinese sets also introduce duplicates of some throws and divide the dominoes into two classes: military and civil. Chinese dominoes
Chinese dominoes
Chinese dominoes are used in several tile-based games, namely, Tien Gow, Pai Gow, Che Deng, Tiu U and Kap Tai Shap. In Cantonese they are called 骨牌 "Gwat Pai", which literally means "bone tiles", it is also the name of a northern Chinese game, where the rules are quite different from the southern...

are also longer than typical European dominoes. Over time Chinese dominoes also evolved into the tile set used to play Mah Jong, a game which swept across the United States in the early to mid 1920s and has enjoyed moderate popularity, especially in its "solitaire" form, since that time. It is played a lot in the Caribbean, especially in Barbados and Jamaica.

The early 18th century witnessed dominoes making their way to Europe, making their first appearance in Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

. The game changed somewhat in the translation from Chinese to the European culture. European domino sets contain neither class distinctions nor the duplicates that went with them. Instead, European sets contain seven additional dominoes, with six of these representing the values that result from throwing a single die with the other half of the tile left blank, and the seventh domino representing the blank-blank (0–0) combination.

Ivory Dominoes were routinely used in 19th century rural England in the settling of disputes over traditional grazing boundaries, and were commonly referred to as "bonesticks" (see Hartley, Land Law in West Lancashire in the mid- 19th Century, Farm Gazette, March 1984).

## Tiles and suits

Domino tiles, also known as bones, are twice as long as they are wide and usually have a line in the middle dividing them into two squares. The value of either side is the number of spots or pips. In the most common variant (Double Six) the values range from blank or 0 (no pips) to 6. The sum of the two values, i.e. the total number of pips, may be referred to as the rank or weight of a tile, and a tile with more pips may be called heavier than a lighter tile with fewer pips.

Tiles are generally named after their two values; e.g. 2–5 or 5–2 are alternative ways of describing the tile with the values 2 and 5. Tiles that have the same value on both ends are called doubles, and are typically referred to as double-zero, double-one etc. Tiles with two different values are called singles.

Every tile belongs to the two suits of its two values, e.g. 0–3 belongs both to the blank suit (or 0 suit) and to the 3 suit. Naturally the doubles form an exception in that each double belongs to only one suit. In 42
42 (dominoes)
42, also known as Texas 42, is a trick-taking game played with a standard set of double six dominoes. 42 is often referred to as the "national game of Texas", and continues to be very popular in much of the state. Tournaments are held in many towns, and the State Championship tournament is held...

, the doubles are treated as an additional suit of doubles, so that, e.g., the double-six 6–6 belongs both to the 6 suit and the suit of doubles.

### Domino sets

The five most common domino sets commercially available are:
Set Tiles Pips
Double-6 28 168
Double-9 55 495
Double-12 91 1092
Double-15 136 2040
Double-18 190 3420

These numbers may be computed quite easily using triangular number
Triangular number
A triangular number or triangle number numbers the objects that can form an equilateral triangle, as in the diagram on the right. The nth triangle number is the number of dots in a triangle with n dots on a side; it is the sum of the n natural numbers from 1 to n...

s: for double-n dominoes, there are tiles and pips. Generally the most commonly used sets are double-6 and double-9, though the other three sets are more popular for games involving several players or for players looking for long domino games.

### Basic rules

Most domino games are blocking games, i.e. the objective is to empty one's hand while blocking the opponents. In the end, a score may be determined by counting the pips in the losing players' hands. In scoring games the scoring is different and happens mostly during gameplay, making it the principal objective.

Block game
The most basic domino variant is for two players and requires a double six set. The 28 tiles are shuffled face down and form the stock or boneyard. Each player draws seven tiles; the remainder are not used. Once the players begin drawing tiles, they are typically placed on-edge before the players, so that each player can see his own tiles, but none can see the value of other players' tiles. Every player can thus see how many tiles remain in the other players' hands at all times during gameplay.
One player begins by downing (playing the first tile) one of their tiles. This tile starts the line of play, a series of tiles in which adjacent tiles touch with matching, i.e. equal, values. The players alternately extend the line of play with one tile at one of its two ends. A player who cannot do this draws another tile from the boneyard until they can use one in the line. The game ends when one player wins by playing their last tile, or when the game is blocked because neither player can play. If that occurs, whoever caused the block gets all of the remaining player points not counting their own.

Draw game
In the Draw game, players are additionally allowed to draw as many tiles as desired from the stock before playing a tile, and they are not allowed to pass before the stock is (nearly) empty. The score of a game is the number of pips in the losing player's hand plus the number of pips in the stock. Most rules prescribe that two tiles need to remain in the stock. The Draw game is often referred to as simply "dominoes".

Adaptations of both games can accommodate more than two players, who may play individually or in teams.

### Line of play

The line of play is the configuration of played tiles on the table. Typically it starts with a single tile, from which it grows in two opposite directions when the players add matching tiles. (In practice the players often play tiles at right angles when the line of play gets too close to the edge of the table.)

The rules for the line of play often differ from one variant to another. In many rules the doubles serve as spinners, i.e. they can be played on all four sides, causing the line of play to branch. Sometimes the first tile is required to be a double, and serves as the only spinner. In some games such as Chicken Foot
Chicken Foot (domino game)
Chicken foot, also known as Chicken dominoes, Chickie dominoes and Chickie, is a dominoes game of the "Trains" family, similar to Mexican Train. Chicken Foot is played in rounds, one round for each double domino in the set...

, all sides of a spinner must be occupied before anybody is allowed to play elsewhere. Matador
Matador is a common game using a set of dominoes. While it is similar to many domino games which the object of the game the first to go out, it has a differing very unusual rule of combining pips instead of matching numbers...

has unusual rules for matching. Bendomino
Bendomino
Bendomino is a tabletop strategy game similar to dominoes, created by Thierry Denoual and published by Blue Orange Games in 2007. It is a set of double-6 dominoes with a 120-degree curve. The main difference from dominoes is the curved shape of the pieces, which introduces a new level of strategy...

uses curved tiles, so that one side of the line of play (or both) may be blocked for geometrical reasons.

In Mexican Train
Mexican Train
Mexican Train, also known as simply Trains, is a game played with dominoes. The object of the game is for a player to play all the dominoes from his or her hand onto one or more chains, or "trains", emanating from a central hub or "station". The game's most popular name comes from a special...

and other Trains games, the game starts with a spinner from which various trains branch off. Most trains are owned by a player, and in most situations players are only allowed to extend their own train.

### Scoring

In blocking games the scoring happens at the end of the game. After a player has emptied their hand, thereby winning the game for their team, the score consists of the total pip count of the losing teams' hands. In some rules the pip count of the remaining stock is added. If a game is blocked because no player can move, the winner can often be determined by counting the pips in all players' hands.

In scoring games each individual move potentially adds to the score. E.g. in Bergen, players score 2 points whenever they cause a configuration in which both open ends have the same value and 3 points if additionally one open end is formed by a double. In Muggins
Muggins (domino game)
Muggins is a domino game played with any of the commonly available sets. The object of the game is for each player to rid their hand of dominoes, and additionally to score points by playing a domino that makes the total number of pips on all endpoints of the board equal to a multiple of...

, players score by ensuring that the total pip count of the open ends is a multiple of a certain number. In variants of Muggins the line of play may branch due to spinners.

In British public houses and social clubs the scoring version of "fives and threes" is used. Score is kept on a cribbage board and the objective is to score 61 points. The points are scored by making totals at the ends of the lines that are divisible by five and three, thus a score of 15 (say double five at one end and a single five at the other) scores a total of eight points (five threes and three fives). If at the end game your score is more than the points remaining you cannot peg out and must wait to score lower (for example if you have 54 and you score 8 points you cannot peg that, so you must wait for the opportunity to score fewer points). This is played in a number of competitive leagues in the British Isles.

### Minor details

In many versions of the game, the player with the highest double leads with that double, for example "double six". If no one has it the next highest double is called - "double five?", then "double four?", etc. until the highest double in any of the players hands is played. If no player has an "opening" double, the next heaviest domino in the highest suit is called - "six - five?", "six - four?". In some variants the players take turns picking dominoes from the stock until an opening double is picked and played; in other variants the hand is reshuffled and each player picks seven dominoes. After the first hand, the winner or winning team of the previous hand is allowed to pick their dominoes first, and begins by playing any domino in his or her hand.

Playing the first bone of a hand is sometimes called setting, leading, downing, or posing the first bone. Dominoes aficionados often call this procedure smacking the bone down. After each hand the bones are shuffled, and each player draws the number of bones required (7). Play generally proceeds "clockwise". The next player, and all players in turn, must play a bone with an end that matches one of the open ends of the layouts. In some versions of the games, the pips or points on the end, and the section to be played next to it must add up to a given number; [For example in a double six set the "sum" would be six, requiring a "blank" to be played next to a "6," a "1" next to a "5", a "2" next to a "4", etc.]

The stock of bones left behind, if any, is called the bone yard, and the bones therein are said to be sleeping. In draw games, players take part in the bone selection, typically drawing from the bone yard when they don't have a "match" in their hand.

Generally, if a player inadvertently picks up and sees one or more extra dominoes, those dominoes becomes part of his or her hand.

A player who can play a tile may or may not be allowed to pass anyway. Passing can be signalled by tapping twice on the table or by saying "go" or "pass".

Play continues until one of the players has played all the dominoes in his or her hand, (and calls "out!", "I win", or "domino!") and wins the hand, or until all the players are blocked and no legal plays are left. This is in some areas referred to as a lockdown or "sewed up". In a common version of the game, the next player after the block, picks up all the dominoes in the bone yard, as if trying to find the (non-existent) match. If all the players are blocked, or locked out the player with the lowest hand / pip count wins. In team play, the team with the lowest individual hand wins. In the case of a tie, the first of tied players or the first team in the play rotation wins.

In games where points are accrued, the winning player scores a point for each pip on each bone still held by each opponent, or the opposing team. If no player went out, however, the win is determined by the lightest hand; sometimes only the excess points held by opponents. A game is generally played to 100 points, the tally being kept with paper
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....

and pencil
Pencil
A pencil is a writing implement or art medium usually constructed of a narrow, solid pigment core inside a protective casing. The case prevents the core from breaking, and also from marking the user’s hand during use....

. In more common games, mainly urban rules, games are played to 150, 200, or 250 points. In some games the tally is kept by creating houses, where the beginning of the house (the first ten points) is a large +, the next ten points are O
O
O is the fifteenth letter and a vowel in the basic modern Latin alphabet.The letter was derived from the Semitic `Ayin , which represented a consonant, probably , the sound represented by the Arabic letter ع called `Ayn. This Semitic letter in its original form seems to have been inspired by a...

, and scoring with a 5 is a /, and are placed in the four 'corners' of the house. In some versions, if a lockdown occurs then the first person to call the lockdown will gain the other players bones and add the amount of the pips to their house. Also, the first person to call rocks if they believe or know the person that called "domino" or "lockdown" miscounted the pips will count the pips themselves; if the person that called rocks finds that the number of pips the player called is different, the points become his after proving that he is correct in his counting.

### Games using more dominoes

With bigger domino sets, especially with the Double Fifteens and Double Eighteens, it is possible to have more players. Double 9s is good for 4 to 6 players and each player would start with 10 dominoes in their hand. Double 12s, 15s, and 18s are good for up to 10 to 15 players, each with 7 dominoes. If you have fewer players and more dominoes, start with more dominoes in each player's hand, but leave enough dominoes in the bone pile to draw from. When using the larger sets, make sure you have plenty of playing room as they can spread out considerably.

Double 6s = 7 rounds, double 9s = 10 rounds, double 12s = 13 rounds, double 15s = 16 rounds, double 18s = 19 rounds.

### Card games using domino sets

Apart from the usual blocking and scoring games, there are also domino of games of a very different character, such as solitaire or trick-taking games. Most of these are adaptations of card game
Card game
A card game is any game using playing cards as the primary device with which the game is played, be they traditional or game-specific. Countless card games exist, including families of related games...

s and were once popular in certain areas to circumvent religious prescriptions against playing card
Playing card
A playing card is a piece of specially prepared heavy paper, thin cardboard, plastic-coated paper, cotton-paper blend, or thin plastic, marked with distinguishing motifs and used as one of a set for playing card games...

s.
A very simple example is a Concentration
Concentration (game)
Concentration, also known as Memory, Pelmanism, Shinkei-suijaku, Pexeso or simply Pairs, is a card game in which all of the cards are laid face down on a surface and two cards are flipped face up over each turn. The object of the game is to turn over pairs of matching cards...

variant played with a double-six set; two tiles are considered to match if their total pip count is 12.

A popular domino game in Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

is 42
42 (dominoes)
42, also known as Texas 42, is a trick-taking game played with a standard set of double six dominoes. 42 is often referred to as the "national game of Texas", and continues to be very popular in much of the state. Tournaments are held in many towns, and the State Championship tournament is held...

. The game is similar to the card game spades
Spades is a partnership trick-taking card game devised in the United States in the 1930s, in which the object is for each pair or partnership to take at least the number of tricks they bid on before play began. Spades is a descendant of the Whist family of card games, which also includes Bridge,...

. It is played with four players paired into teams. Each player draws seven dominoes, and the dominoes are played into tricks. Each trick counts as 1 point, and any domino with a multiple of 5 dots counts toward the total of the hand. 35 points of "five count" + 7 tricks = 42 points, hence the name.

## Competitive play

Dominoes is played at a professional level, similar to poker. Numerous organisations and clubs of amateur domino players exist around the world. Some organisations, including the International Federation of Dominos and the Fédération Internationale de Domino (FIDO), organise international competitions. The 2008 and 2009 Double FIDO domino world champion from the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

is Darren Elhindi.

## Other uses of dominoes

Besides playing games, another use of dominoes is standing them on end in long lines so that when the first tile is toppled, it topples the second, which topples the third, etc., resulting in all of the tiles falling. For large and elaborate arrangements, special blockages (also known as firebreaks) are employed at regular distances to prevent a premature toppling from undoing more than a section of the dominoes while still being able to be removed without damage.

Arrangements of millions of tiles have been made that have taken many minutes, even hours to fall. By analogy, the phenomenon of small events causing similar events leading to eventual catastrophe is called the domino effect
Domino effect
The domino effect is a chain reaction that occurs when a small change causes a similar change nearby, which then will cause another similar change, and so on in linear sequence. The term is best known as a mechanical effect, and is used as an analogy to a falling row of dominoes...

. The phenomenon also has some theoretical relevance (amplifier
Amplifier
Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...

, digital signal
Digital signal
A digital signal is a physical signal that is a representation of a sequence of discrete values , for example of an arbitrary bit stream, or of a digitized analog signal...

, information processing
Information processing
Information processing is the change of information in any manner detectable by an observer. As such, it is a process which describes everything which happens in the universe, from the falling of a rock to the printing of a text file from a digital computer system...

), and this amounts to the theoretical possibility of building domino computer
Domino computer
A domino computer is a mechanical computer built using dominoes to represent mechanical amplification or logic gating of digital signals. Because of the existence of multiple schemes, domino computer will be used in this article as a collective noun, denoting any particular scheme that uses the...

s. Dominoes are also commonly used as components in Rube Goldberg machine
Rube Goldberg machine
A Rube Goldberg machine, contraption, device, or apparatus is a deliberately over-engineered or overdone machine that performs a very simple task in a very complex fashion, usually including a chain reaction...

s.

The Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

has hosted an annual domino toppling exhibition called Domino Day
Domino Day
Domino Day was a world record attempt for the highest number of toppling domino stones, organized from 1998-2009 by Endemol Netherlands. Together with Weijers Domino Productions of Robin Paul Weijers, also known as Mr. Domino, parties teamed up to set a new world record...

since 1986. The event held on November 18, 2005 knocked over 4 million dominoes by a team from Weijers Domino Productions. On Domino Day 2008 (November 14, 2008), the Weijers Domino Productions team attempted to set 10 records:
1. Longest domino spiral (200 m)
2. Highest domino climb (12 m)
3. Smallest domino tile (7 mm)
4. Largest domino tile (4.8 m)
5. Longest domino wall (16 m)
6. Largest domino structure (25,000 tiles)
7. Fastest topple of 30 metres of domino tiles (4.21 sec, time by Churandy Martina: 3.81 sec)
8. Largest number of domino tiles resting on a single domino (1002 tiles) for more than 1 hour
9. Largest rectangular level domino field (1 million tiles)
10. A new record of 4,345,027 tiles

This record attempt was held in the WTC Expo hall in Leeuwarden. The artist who toppled the first stone was the Finnish
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

acrobat
Acrobatics
Acrobatics is the performance of extraordinary feats of balance, agility and motor coordination. It can be found in many of the performing arts, as well as many sports...

Salima Peippo.

At one time, Pressman Toys manufactured a product called Domino Rally
Domino Rally
Domino Rally was a toy product manufactured by Pressman Toys in the 1980s and early 1990s.Originally named "Domino Track" and designed by Jason Carroll, a 16-year-old boy, assisted by his father. The design was submitted to American Idea Management...

that contained tiles and mechanical devices for setting up toppling exhibits.

In Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

on November 9, 2009, giant dominoes were toppled in a 20th anniversary commemoration of the fall of the Berlin Wall. Former Polish president and Solidarity leader Lech Wałęsa
Lech Wałęsa
Lech Wałęsa is a Polish politician, trade-union organizer, and human-rights activist. A charismatic leader, he co-founded Solidarity , the Soviet bloc's first independent trade union, won the Nobel Peace Prize in 1983, and served as President of Poland between 1990 and 95.Wałęsa was an electrician...

set the toppling in motion.

A similar physical phenomenon can be seen in Newton's cradle
Newton's cradle, named after Sir Isaac Newton, is a device that demonstrates conservation of momentum and energy via a series of swinging spheres. When one on the end is lifted and released, the resulting force travels through the line and pushes the last one upward...

.

## Dominoes in Unicode

Since April 2008, the universal text encoding standard Unicode
Unicode
Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...

includes characters that represent the double-six domino tiles in various orientations (all combinations of 0 through 6 pips on the left or right provides 7x7 or 49 glyphs, the same combinations vertically for another 49, and also a horizontal and a vertical "back" for a total of 100 glyphs). The Unicode range for dominoes is U+1F030 .. U+1F09F. (Grey areas in the table below indicate non-assigned code points.) However, few fonts http://www.fileformat.info/info/unicode/block/domino_tiles/fontsupport.htm are known to support these glyphs.

## Historic domino competitions

• Col. Henry T. Titus vs. Capt. Clark Rice for the naming of Titusville, Florida
Titusville, Florida
Titusville is a city in Brevard County, Florida in the United States. It is the county seat of Brevard County. Nicknamed Space City, USA, Titusville is on the Indian River, west of Merritt Island and the Kennedy Space Center and south-southwest of the Canaveral National Seashore...

• Board games
• Chinese dominoes
Chinese dominoes
Chinese dominoes are used in several tile-based games, namely, Tien Gow, Pai Gow, Che Deng, Tiu U and Kap Tai Shap. In Cantonese they are called 骨牌 "Gwat Pai", which literally means "bone tiles", it is also the name of a northern Chinese game, where the rules are quite different from the southern...

• Domino Theory
Domino theory
The domino theory was a reason for war during the 1950s to 1980s, promoted at times by the government of the United States, that speculated that if one state in a region came under the influence of communism, then the surrounding countries would follow in a domino effect...

• List of world championships in mind sports
• Pub games
Pub games
Pub games are games which are or were played in pubs, bars, inns, and taverns, particularly traditional games played in English pubs. Most are indoor games, though some are played outdoors Pub games are games which are or were played in pubs, bars, inns, and taverns, particularly traditional games...