Domino, also called dominoes or domination, is a game of chance and skill in which players set up pieces of a rectangular block on a flat surface, usually a table. Each piece bears one to six identifying marks or spots, called pips, and is blank on the other side. The pips and the pattern of markings on each end of the domino mark its identity, and the number of dots on each piece determines its rank in a line of play. Some games require a complete domino set, while others are played with partial sets and only certain of the pieces in a given set.

Domino has been around for more than a century and is one of the most popular board games in the world. It has also been used for educational purposes, and it has become an important tool in the study of probability and statistics. In recent years, domino has gained renewed popularity as a social activity with family and friends, both young and old.

A standardized domino set is composed of 28 tiles, and it may be used to play a variety of different games. Each player picks a tile, and the first person to make a play begins the sequence of the game. The player who draws the heaviest tile makes the first move. After the heaviest tile is laid down, the next player adds to the sequence by playing a matching tile to it. The game continues until the line of play is completed or the losing players chip out, which means that they have no more tiles to lay.

The word domino was derived from a Latin term meaning “to command.” Although many domino games involve skill, the basic rules are the same in all games. The rank of each domino is determined by its arrangement of pips and the number of pips on each end. The higher the rank, the more points a domino will score when it is added to a chain of adjacent dominoes.

When Lily Hevesh started collecting dominoes at age 9, she loved setting them up in a straight or curved line and flicking the first one to see it fall, one by one. She quickly became an expert, and now her YouTube channel, Hevesh5, has more than 2 million subscribers. She’s also created elaborate domino setups for movies, TV shows, and events—including an album launch for pop artist Katy Perry.

Before Hevesh knocks over one of her creations, she tests each part of the setup in slow motion to ensure that it will work as intended. This process of testing, or prototyping, allows her to make precise corrections as needed.

Dominoes have inertia, a tendency to resist movement when no external force is applied to them. A small nudge, however, is all it takes to push the domino past its tipping point and begin the cascade. Similarly, it takes a small commitment to a new behavior—making your bed, for example—to build the identity-based habits that lead to bigger changes in your life.