Dominoes (or dominos) 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 and polyominoes, the word domino often refers to any rectangle formed from joining two congruent squares edge to edge. The traditional Sino-European domino set consists of 28 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, nips or dobs) 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, in that a variety of games can be played with a set.

The earliest mention of dominoes is from Song Dynasty China, found in the text Former Events in Wulin. Dominoes first appeared in Italy during the 18th century, and although it is unknown how Chinese dominoes developed into the modern game, it is speculated that Italian missionaries in China may have brought the game to Europe.

With a standard set of dominoes, running from double-blank to double-six, fortunes can be read according to the traditional interpretations that follow.

In procedure, the dominoes are placed with their spots downward and are thoroughly mixed about before one is chosen. Some diviners insist on taking the most distant domino, but others feel that fate provides the guiding hand in any case, so either process may be used.

All agree, however, that no one should seek to learn his fortune by this method more than once a month, as the answers will then be meaningless, or even worse, may result in an adverse fulfillment.

Three dominoes are also the prescribed limit for an individual, within that period, or at a single sitting. Any domino drawn should be interpreted, then replaced and thoroughly   mixed with the rest, before another is drawn. If the same domino should come up twice for a person, it is a strong confirmation of its original finding. In that case, the individual

is also allowed to draw another domino beyond the prescribed three. Some students of domino lore refuse to consult them on Mondays or Fridays, claiming that those are bad days that produce doubtful divinations. That rule may not really matter, but those who follow it will have the satisfaction of being on the safe side.