Domino is a game played with a set of small rectangular blocks with a pattern of dots on one face, called pips, which resemble those on dice. They are typically glued together with a thin coating of wax. A domino is played on a flat surface, such as a table or floor, and the end of each domino is left open to allow for linking adjacent tiles with each other into a chain or string of play. Dominoes may be played by two or more players, and the game can be won either by reaching a pre-determined point total or by outlasting opponents over many rounds.
There are a variety of different domino games, each with slightly different rules. Some are designed to be played with a specific number of players (usually from four to eight), while others are designed to be competitive. In addition, the way in which a domino is played can vary widely between cultures and from one region to another.
The game of domino has evolved from its original form as a simple counting and scoring activity to an art form involving precise placement and manipulation of the pieces. The game has also inspired a number of artistic and literary works.
In the past, domino sets were made from a wide variety of natural materials: bone, silver lip ocean pearl oyster shell (mother of pearl), ivory, and dark hardwoods such as ebony, with contrasting black or white pips inlaid or painted on each piece. More recently, plastic has become the primary material used for domino sets due to its lower cost and better durability.
After the dominoes are shuffled and a player is determined to make the first play (this may be by drawing lots, by the order in which hands are drawn, or by the rule of the particular game), the player places a domino down. This domino is known as the set, down, or lead. The player who plays the next domino, or adds to the line of play, is then called the ender.
A tile played to a domino with matching ends must touch that domino squarely and entirely at both of its ends. This allows the line of play to develop into a snake-like shape, forming patterns ranging from straight lines to curved ones, or even grids that form pictures when the dominoes fall.
Regardless of the specifics of the line of play, each domino placed in this manner must have its matching open end facing toward the ender or another domino. For example, a domino played to a double 6-6 must have its open end facing the ender or the other domino; however, due to space constraints or on a whim, a tile played to a double 6-6 can be connected at an angle, creating an L-shaped line of play.
As the line of play continues to grow, each domino must be positioned so that it touches its matching open end squarely. This configuration is referred to as the layout, string, or line of play.