A domino is a tile with one or more pips (also called spots) that indicate a value of zero, 1, 2, 3, 4, 5, 6, 7, 8, or 9. Dominoes are usually twice as long as they are wide. The pips are inlaid or painted on both sides of the domino. Most domino sets contain 28 tiles, although larger ones are available for games involving several players or for those who want to play longer lines of dominoes. There are two main types of domino games, blocking games and scoring games.

Blocking games are those in which one domino is placed on the table and its pips are counted as the player draws. Then, each other player plays a domino that matches one of the open ends of the previous tile. If a player cannot match an end of their own domino to the existing one, they must draw a new tile from the unused stock (also known as the boneyard). The first player to finish playing all of their own tiles wins.

The most basic game of blocking domino uses a double-six set. The dominoes are shuffled and then each player draws seven of their own tiles from the stock. The player with the most pips on their tiles is the leader and decides which of their pieces will be played first.

Dominoes are a classic family activity. The youngest members of a household can enjoy building simple structures with the tiles, and older children are often fascinated by the possibilities for intricate designs that can be made from stacking them on end in long lines. A domino can be tipped over and cause the rest of the line to topple, creating a chain reaction that is fun to watch. Creating these complex structures is also a great way to practice math and engineering skills.

Lily Hevesh, a 20-year-old from Michigan, has been obsessed with dominoes since she was 9. She began posting videos of her own creations to YouTube and quickly became a professional domino artist who creates spectacular setups for movies, TV shows, and events. She has worked on projects involving more than 300,000 dominoes and has millions of fans on her YouTube channel.

When Hevesh starts working on a large-scale project, she usually tests out each individual section of the layout by placing them on a flat surface. She then lays the sections in place and adds the lines that connect them. Hevesh takes a lot of time to plan out each project before starting. She often films the tests in slow motion to catch any mistakes and make adjustments.

The word domino has had other meanings in English, including a hooded cloak worn together with a mask during carnival season or at a masquerade and, earlier, a black cape worn by a priest over his surplice. However, the modern usage is most closely related to the word dominoes. The modern usage dates from the late 18th century.