Dominoes are small rectangular blocks of wood or plastic, each marked with an arrangement of dots resembling those on dice. The dominoes used in games are sometimes called bones, pieces, men, or stones. They are used for a variety of games that fall into two categories: blocking and scoring. Each domino has an identity-bearing face that is blank or patterned identically on both sides and a non-identity-bearing side that is either white or colored (see illustration below). The most common domino sets are double six and double nine, with 28 and 55 tiles respectively. Larger sets exist, however, and are used for games involving several players or those who wish to play long domino chains. The domino is one of the simplest and most popular gaming devices. Its simple rules allow for a huge variety of variations, making it ideal for children’s games. It is also an excellent way for people with limited physical skills to learn and practice the basic fundamentals of game play. There are a number of different domino games, which vary according to the rules set forth by each individual game’s author or designer. Many of the games found on this site follow standard general rules, but there are some that have very specific requirements governing the way the dominoes must be played. These special requirements are noted in the individual games’ descriptions. Most of the games played with dominoes involve a line of dominoes that is formed by matching the pips on their open ends. This is known as the line of play. In some games, the player who makes the first play must draw a tile from the stock and then place it in the line of play. In other games, the player may ‘buy’ a tile from the stock, depending on the rules of the particular game being played. When a domino is standing upright, it has potential energy, which means that the domino’s pips are touching but not yet connected. When the domino is struck or otherwise tripped, its potential energy converts to kinetic energy, which causes the domino to fall and cause other dominoes to topple as they are struck. It is this chain reaction that constitutes a domino game. Dominoes have a long history of use, both as a playing device and as symbols of power. In the early 20th century, dominoes were a popular pastime for both young and old alike, especially in Latin America. As a result, dominoes are still widely available and are often seen in public places such as schools and libraries. Lily Hevesh, 20, is an accomplished domino artist who has become famous for her incredible domino setups that she creates in straight and curved lines on a table. She has more than 2 million YouTube subscribers and has been hired to create domino setups for movies, TV shows, and events. Her hobby has turned into a successful career, and she now travels the world creating unique domino art.