Domino, the popular game of setting up a line of dominoes and then flicking one to cause them all to fall in a cascade, illustrates how a simple action can trigger an entire sequence of events. It’s a concept that can be applied to any activity—even writing.

Lily Hevesh, 20, first started playing with dominoes when she was 9 years old. Her grandparents had a classic 28-piece set, and she loved to place them in straight or curved lines, then flick them to see the chain reaction. Her fascination with dominoes grew into a career as a professional domino artist. Her YouTube channel, Hevesh5, has more than 2 million subscribers.

Hevesh says there is one physical phenomenon that’s essential to creating a great domino setup: gravity. A domino has inertia, a tendency to resist motion unless there is a force pushing or pulling on it. When Hevesh sets up her massive designs, she nudges the first domino just past its tipping point. This tiny nudge releases the potential energy that was stored in the piece, which causes it to fall and push on the next domino in the chain.

While most people think of a domino as a rectangular block bearing from one to six pips or dots, there are also square and hexagonal dominoes. The earliest dominoes were made of wood, but today they are most commonly made of plastic or clay. The most common dominoes are rectangular, with either a white or black background. Most dominoes have a number on one end, indicating its suit. Each suit corresponds to a particular number; for example, the threes are in the suit of threes and the blanks or 0s are in the suit of 0.

The most common commercial domino sets are double-six and double-nine. Larger sets exist, but they are not as readily available. Many of these larger sets have more than 20 pieces, which can make the games very difficult to play with only four players. Dominoes can be used for a variety of games, including blocking and scoring games. There are also layout games, which are played on a flat surface and consist of long chains of tiles. Some of these games are adaptations of card games and were popular to circumvent religious proscriptions against playing cards.

The term “domino” comes from the Latin word dominum, meaning “rule” or “control.” It’s used to describe a system that has gained or maintained control over another, such as a political or economic power struggle. The first recorded use of the word was in a book published in 1750 by the French mathematician Blaise Pascal, who created a mathematical model for the game of domino. The word has since come to be used as a synonym for any system that gains or maintains control over others, including businesses and societies.