What does cardinality refer to in mathematics?

Cardinality in mathematics refers specifically to the number of elements in a set or grouping. It is a fundamental concept in set theory, where the cardinality of a finite set indicates how many distinct objects or elements it contains. For instance, if a set has three elements, its cardinality is three.

This concept is crucial for understanding various mathematical topics, including counting, comparing sizes of different sets, and even in more advanced topics such as infinite sets. The precise determination of cardinality allows mathematicians to classify sets based on size, applying these principles in various fields including probability and statistics.