The domino effect is the phenomenon by which one event causes a chain reaction that results in other events, in which the first is a catalyst for subsequent ones. The term is most often used in relation to the falling of dominoes, but it can apply to many different kinds of events. For example, when someone changes a habit, such as exercising more, it can lead to other positive habits like eating healthier. In such cases, the change may not be intentional; it could just be a matter of reducing sedentary leisure time and then changing eating habits as a natural side effect.
Dominoes are a type of flat, rectangular block game piece that are typically made of ivory or bone, silver-lip ocean pearl oyster shell (mother of pearl), wood, or plastic and have a characteristic marking on the face, which is often divided into two square halves each marked with an arrangement of dots, or “pips,” similar to those on a die, except that some squares are blank. Each pips represents a number, but the absence of pips means zero. The majority of domino games are based on positional play where each player in turn places a domino edge to edge against another such that the adjacent faces are identical or form some specified total, for instance, all of the same numbers.
When playing domino, players set out the tiles on a table. Each tile must be positioned so that one end of the tile matches one of the ends of the other tiles in the layout, or it is placed to the left or right of an existing tile such as a 6-6 that has open ends of 5 and 6. The dominoes must then be connected together to form a chain of alternating doubles and singles. The shape of the chain then develops a snake-like appearance.
In addition to the basic blocking and scoring games, a wide variety of other games can be played with dominoes, including some that duplicate card games so as to circumvent a religious prohibition against playing cards. Some of these involve counting the pips on opponent’s remaining dominoes, while others determine winning players by awarding them the number of pips on opposing players’ surviving tiles.
While the majority of dominoes are manufactured from polymer materials, some sets are made of more natural substances such as stone (usually marble or granite); other types of woods (usually oak or redwood); metals such as brass or pewter; and ceramic clay. Generally, such sets are less expensive than those made of polymer and have a more attractive look.
Dominoes can also be found in a wide range of colors. Most standard sets have white dominoes with black pips, but they can be produced in almost any color combination. There are even some sets that have a top half of mother of pearl or ivory with a contrasting ebony black lower section. In some cases, the pips are inlaid or painted rather than molded; the result is a unique, high-quality product.