Set that includes two distinct elements.

It’s important to distinguish between a pair of elements like {3, 6}, and an ordered pair of elements like (3, 6).

### Notation

The elements in a pair are written between braces and we do not consider the order in which the elements are written, because it is a set.

### Examples

- The sets {3, 5} and {–6, –9} are pairs.
- The pairs {2, 3} and {3, 2} are equal.