Domino, also known as bones, cards, men, stones or tiles, are rectangular blocks of wood or plastic that are stacked on end and used to play games. Each domino has a line in the middle that separates it into two squares, one of which has a number of spots—called pips—and the other is blank or identically patterned. Dominoes are often arranged in long lines, and when the first one is knocked over, it triggers a chain reaction that continues until all the dominoes have fallen.

Many different types of domino games exist, and there are a wide variety of ways to use them in educational settings. The most common include bidding games, blocking games, scoring games and round games. In the case of bidding games, players compete to be the first to place a tile on the board, while blocking and scoring games focus more on strategy than competition.

In a typical domino game, each player has a hand of dominoes and takes turns playing a tile. After each play, a domino may be removed from the board or set aside, depending on the rules of the game. When a player has no more tiles to play, he or she “calls out” and the next player takes his turn. In some games, the last player to play a tile wins.

Each domino has potential energy, a property that causes it to resist motion when no outside force is pushing on it. Once a domino is pushed past its tipping point, however, the energy in the tile converts to kinetic energy and transmits to the next tile. Then that tile converts the kinetic energy into a new kind of energy, called rotational energy, which causes it to spin around and eventually knock over the next domino.

The way a domino is arranged, or the “line of play,” determines how the game is played. For example, the dominoes can be stacked in straight or curved lines, grids that form pictures when they fall, stacked walls or 3-D structures like towers and pyramids. A line of play can be set up on any surface, but it is easier to move the dominoes over a smooth, flat surface.

The number of pips on each end of the dominoes can also determine how a game is played. Some domino sets have a fixed number of pips per end, while others have varying numbers of pips on each end. In general, a higher number of pips on a single end means a stronger tile.