Domino is a game in which players take turns placing domino tiles on the table until a complete line, or string, is formed. Each domino has a number of spots or dots, called pips, which indicate its identity. Some dominoes also have a blank or identically patterned side. A player begins a round by drawing one of the dominoes from the stock. The domino drawn determines seating arrangements for that round. The player who draws the heaviest domino makes the first play. The player who draws the next highest domino seats himself to his left. The remaining players draw additional dominoes for their hands and play continues.

A domino set consists of the number of individual dominoes specified by the rules for the specific game being played. Depending on the rules, a domino may be double or single. A domino cannot be stacked on top of another domino. A domino may be a spinner, which is a domino with an open end that can be played against another domino on any side. Some games allow a player to make a spinner on the opening turn, while others require that a player must make a spinner as his first play in every turn thereafter.

In the case of a tie, some games provide for breaking the tie by drawing new dominoes from the stock to begin play. The winner of the previous game opens the next game. Often the winners are the partners whose combined total of pips in their remaining dominoes is the least.

The speed at which a domino falls depends on how much external force is applied to it. A domino that is not touching anything else moves very slowly, while a tumbling domino has a great deal of energy. A domino that is pushed from behind or pulled from the sides has even more potential energy.

Although dominoes are commonly made of polymer clay, they can be crafted from many other materials. Some sets have been carved out of stone (such as marble, granite or soapstone); woods such as ebony and bone; metals; and ceramic clay. These natural materials lend a more elegant look to the finished product and usually command higher prices than those constructed of polymer clay. In addition, they are typically heavier in weight than polymer-based dominoes.