Set equality occurs when two sets contain exactly the same elements, regardless of the order or the number of times those elements appear. For example, the sets 1, 2, 3 and 3, 2, 1 are considered equal because they have the same elements. However, the sets 1, 2, 2, 3 and 1, 2, 3 are also equal, as duplicates do not affect set membership. To denote set equality, we use the symbol "=". If two sets are equal, we can say that they are identical in terms of their elements. This concept is fundamental in mathematics and is essential for understanding more complex topics like set theory and functions.