A domino is a small, flat, thumb-sized rectangular block used as a gaming object. A domino set features a number of tiles, or aces, each bearing from one to six dots or pips (or other marks), and the pieces are usually laid down in a line or angular pattern. Dominoes are often played in a sequence, with the goal of setting up a chain reaction that will cause the last remaining domino to fall. The word “domino” and the game itself appear to have originated in France shortly after 1750. The word had earlier denoted a long hooded cloak worn together with a mask during carnival season or at a masquerade. The name may be a reference to the garment’s black color contrasting with the white surplice of a priest, or it could refer to the admonition of “Do not touch!” that was printed on the hood.
Dominoes are also a fun way for children to practice their math skills as they arrange the aces into rows and columns. Depending on the age of the child, they may also be taught to count the pips or spots on each domino before attempting to place it correctly. For older players, the challenge of setting up the most complex domino cascades can be exciting and rewarding. The most common domino sets feature a total of 28 numbered tiles, although extended sets with more than that number of aces exist.
The most popular type of domino play involves blocking games, which are played by identifying the end of each tile and arranging them in lines or angular patterns. Each domino belongs to one of two suits: the suit of a particular number, or the suit of blanks or zeroes. Some large domino sets use more readable Arabic numerals on the aces rather than pips.
In writing, the domino effect can help a writer hone her craft and achieve a sense of pace and logic in her scenes. If a scene runs against the reader’s expectation for what should happen next, it will feel jarring or out of character and the story may stall. On the other hand, a sequence of dominoes that advance the hero toward or closer to her goal will heighten tension and keep readers engaged.
A domino’s inertia makes it difficult for it to move until some force, such as a nudge, is applied. The energy in a domino that is standing upright is called potential energy. When it falls, this potential energy is converted into kinetic energy, which causes other dominoes to topple in a chain reaction. The speed at which a domino pulse moves is comparable to the speed of nerve impulses that travel down an axon.