Domino is a game played with small flat blocks, each bearing one to six pips or dots. Twenty-eight such pieces make up a complete set of dominoes. A player sets up the dominoes in a line or a zigzag pattern, then flips the first one and lets it fall over the next to cause an entire chain reaction. The player then has the option to continue the pattern or to stop, depending on his or her strategy.

The word domino comes from the Latin dominium, meaning a place of control. In the past, it also meant a large area of influence or dominance, as in a territory under military occupation by another force. Today, the word domino is used more generally to refer to a sequence of events or actions.

For example, a person may build an email list to grow their business and write articles to increase online exposure and run live events to gain trust with potential clients. All of these tasks work together to create a lead domino that brings in more business over time.

The most common material for dominoes is a type of polymer known as acrylonitrile butadiene styrene (ABS). Aside from ABS, there are several other kinds of plastics that can be used to make dominoes. These include polyvinyl chloride (PVC) and styrene butadiene acrylonitrile plastic (SBA). The latter is more commonly found in commercial domino sets.

Aside from the plastic materials, dominoes can be made of other natural substances as well. For example, some sets of European-style dominoes are made of silver lip ocean pearl oyster shell (mother of pearl), ivory, or a dark hardwood such as ebony with contrasting black or white pips inlaid or painted. These sets have a more elegant look and often weigh more than those made of polymer plastics.

In addition to their entertainment value, dominoes have a number of practical uses, including teaching children basic math and vocabulary. For example, a teacher can use a domino to demonstrate the commutative property of addition. For instance, the teacher can choose a domino at random and name the dot pattern on it (2+4=6). Then the student can draw the same dot pattern on another domino and add the two numbers to create an equation. The lesson can then be repeated with other dominoes to reinforce the concept of adding and subtracting. In this way, students can see how the commutative property of addition is applied in real-world situations. The same concept can be taught using a variety of other types of moveable manipulatives, such as cubes and counters. This is especially beneficial for students with a variety of learning styles and abilities. It can also be an effective strategy for closing the achievement gap.