Union of Sets
The union of two sets, denoted A∪B (" A union B "), is the set of all members contained in either A or B or both. We can think of the union of two sets as the entire Venn diagram:
Intersection of Sets
The intersection of two sets, denoted A∩B (" A intersect B ") is the set of all members contained in both A and B . We can think of the intersection of two sets as the overlap in the Venn diagram:
When two events (call them "A" and "B") are Mutually Exclusive it is impossible for them to happen together: