Sets and Notation: A set is a collection of unique elements, represented with capital letters and curly brackets. In Venn diagrams, the universal set (U) contains all possible elements.

Venn Diagrams: Visually represent relationships between sets. Overlapping areas indicate shared elements (e.g., students liking both chocolate and vanilla).

Union and Intersection: The union (A or B, $A \cup B$) combines all elements in both sets, while the intersection (A and B, $A \cap B$) includes only shared elements.