Dominoes 03-01 (reversed) pairs, and generic backsides. Dominoes Dominoes is a family of tile-based games played with rectangular "domino" tiles. 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. The domino gaming pieces make up a domino set, sometimes called a "deck" or "pack". The traditional Sino-European domino set consists of 28 dominoes, featuring all combinations of spot counts
Dominoes involves standing them on end in long lines so that when the first tile is toppled, it topples the second, which topples the third, etc., resulting in all of the tiles falling. By analogy, the phenomenon of small events causing similar events leading to eventual catastrophe is called the domino effect. Arrangements of millions of tiles have been made that have taken many minutes, even hours to fall. For large and elaborate arrangements, special blockages (also known as firebreaks) are employed at regular distances to prevent a premature toppling from undoing more than a section of the dominoes while still