A domino is any of 28 small oblong pieces with a number of pips in one half and blank or identically patterned in the other, used to play games where the players try to make lines of adjacent sides of all their tiles that add up to some specified total. Dominoes have been in wide use for over a century and were originally developed to circumvent religious proscriptions against playing cards. In the game of domino, each player in turn places a single domino edge to edge with another piece already placed. Then the other players try to match the value of their own tiles with that of the first tile in the line. The first player to do so wins the game.
The first domino that falls sets off a chain reaction. The kinetic energy of the falling domino converts to electrical energy that is transmitted along the domino’s axon-like spine, and then to the next domino that is struck and so on. Eventually all the dominoes in the line will fall.
Dominoes can be set up in many different ways to create amazing art. Some examples include straight lines, curved lines that form pictures when they fall, stacked walls and 3D structures like towers and pyramids. Creating these setups requires creativity, planning and precision. A domino designer can start by brainstorming images and ideas, then calculate how many dominoes are needed for the desired effect. Then the designer creates a detailed plan, including arrows showing how the dominoes should be placed and what order they should fall in. Finally, the designer carefully executes the plan and checks the results to ensure that the dominoes have fallen in the correct order.
As the number of dominoes in a line grows, it becomes harder to identify individual ones. Some dominoes have a more distinctive shape than others, and some are marked with the identifying pips in larger numbers to be easier to read. Often, large sets of dominoes are printed with more readable Arabic numerals rather than the traditional pips.
In addition to the standard block and draw games, there are a number of other domino variants that have very different rules and objectives. Many of these are adaptations of card games that were popular at times to circumvent religious proscriptions against playing them.
The most basic of these is the Block game for two players. This game requires a double-six set from which each player draws seven tiles; the remainder is not used. The heaviest of the tiles (usually a double) is the “opening” domino that starts the line of play. The players then take turns extending it with one matching tile at either of its ends. A player who cannot do so passes. The game continues until one player wins the entire line of play or the block is blocked. The winner is rewarded with the total of the remaining pip count of the losing hand.