Dominoes are a generic gaming device, like playing cards or dice, that can be used to play many different games. They are similar to playing cards in that each domino has identifying marks on one side and blank or identically patterned on the other, but they differ from cards because the dominoes are shaped differently. The identifiers on the dominoes are arranged in rows of alternating black and white squares, called “pips,” which indicate the value of the individual domino.
The first step in any domino game is to place the heaviest domino in your hand on top of the remaining set. This is referred to as an opening double and it sets the pattern for the rest of the hand. In most games, each player takes turns placing a domino so that the number on the end of the domino matches an adjacent domino (i.e., 5 to 5) or forms some other specified total. The first person to complete this process wins the hand. A single domino can be placed at a 90 degree angle to another domino in the line of play, but you cannot play on the ends of a double once it is played.
A typical domino set has twenty-four tiles that each have an arrangement of pips on one side and are blank or identically patterned on the other. There are several different kinds of domino sets, but the most common is a double-six set. In addition to the standard domino set, many people have a set of “extended” or “multi-color” dominoes that can have a maximum of twelve pips on an end and thus hold more tiles in a sequence.
There are countless variations of domino games, and the rules for each depend on the type of game being played. The most extensive book containing the rules for all of them is The Great Book of Domino Games by Jennifer A. Kelley. The most basic rule of any domino game is to play a bone in your turn that matches the number on an adjacent domino, except for doubles, which are played across a line of play. If you cannot play a bone in your turn, you must knock the table so that everyone can see your remaining dominoes, then wait until another player makes a playable domino.
A domino aficionado will often refer to this procedure as setting, leading or posing the bone. In teams, the winners are the partners whose combined sum of all spots on their remaining dominoes is lowest. Some games may require all players to chip out, and when this occurs the game is over. In other games, play continues until a player cannot continue and the winner is the partner who has the most chips left in their hands. For any multiple of five in the opponents’ hands, that player receives a score. This is a way to add an element of strategy and competition to the game.