A zero-sum game is a type of game or situation in which the total amount of resources or benefits that are available is fixed, and one person's gain is always equal to another person's loss. This means that if one person wins, another person must lose an equal amount.
For example, imagine that you and your friend are playing a game where you each have 10 coins. The game is a zero-sum game because there are a fixed number of coins, and if you win some of your friend's coins, they will lose an equal number of coins. If you win 5 of your friend's coins, for example, they will lose 5 coins and you will gain 5 coins, so the total number of coins will remain the same (10 coins).
Zero-sum games are often used in economics and game theory to model situations where there is a limited amount of resources or benefits, and competition for those resources or benefits can lead to conflict or rivalry. Understanding zero-sum games can help people to think more carefully about how they approach such situations and to try to find ways to cooperate and work together to maximize the overall benefits.