Dominoes are small rectangular pieces of wood, plastic or metal that have identifying marks on one side and blank faces on the other. These pieces are usually twice as long as they are wide. The number of pips on each end ranges from six in the most common domino set (double-six) to zero or blank on some sets.

Often referred to as “bones,” “cards,” or simply “tiles” these pieces can be played in a variety of ways. Some children like to line them up in rows and knock them down, while others use them as a game board.

Some sets are made of natural materials, such as stone or wood; some are synthetic. Polymer-made sets are less expensive than traditional wooden or bone dominoes, but they are not as durable.

Other sets are made of glass, ceramic clay or frosted glass. They are often more aesthetically pleasing than traditional sets and may be more durable, but are also more expensive.

A number of carved or inlaid sets are available, some with a smooth or polished finish. Some are made of silver lip ocean pearl oyster shell (MOP), ivory or bone. Other sets have a dark hardwood such as ebony, with contrasting black or white pips.

In Europe, dominoes are typically made of bone or silver lip ocean pearl oyster shell (MOP). Some sets feature the top half of the tile in MOP and the lower half in a more natural material such as ivory or bone. Other sets are made of hardwood, with the pips inlaid or painted on.

Several traditional European-style dominoes, particularly those that were used in the 19th century, are carved or inlaid from bone. They have a thicker top half than the bottom, with a recessed area to hold the pips in place. These are often used in games where a high-quality look is important.

They are also sometimes used in a game called 5s-and-3s, where the objective is to attach a domino to a previously played domino such that the sum of the two tiles is divisible by five or three. The first player to accomplish this score one point.

Another popular game is Draw, a two-player game of dominoes. In this version, the first player to play a doublet scores a point for that doublet. The next four tiles played against that doublet must then form a cross, and the player who can do so wins the game.

Players may also choose to play a game called 5s-and-3s, which is similar to Draw but with a different starting doublet. In this game, players try to attach a domino from their hand to the end of an existing doublet so that the sum of the tiles is divisible by five or three.

A special version of Draw, known as the Thierry Denoual game, is played with a double-six domino set that has been bent into a 120-degree curve. Each tile has a curved back, so it can be assembled into a circle that allows either end to block or both ends to connect.