The notation "A ∩ B" represents the intersection of two sets, A and B. This means it includes all elements that are common to both sets. For example, if A contains the numbers 1, 2, 3 and B contains the numbers 2, 3, 4, then the intersection A ∩ B would be 2, 3. In set theory, the intersection is a fundamental concept used to analyze relationships between different groups. It helps in identifying shared characteristics or elements. Understanding intersections is essential in various fields, including mathematics, statistics, and computer science, where data analysis often involves comparing different sets.