Definition:Ordered Pair

Definition
The definition of a set does not take any account of the order in which the elements are listed.

That is, $\set {a, b} = \set {b, a}$, and the elements $a$ and $b$ have the same status - neither is distinguished above the other as being more "important".

Also known as
Some sources call this just a pair, taking the fact that it is ordered for granted.

However, this allows confusion with the concept of a doubleton set, so this usage is not recommended.

Some sources use the term ordered double.

Also see

 * Equivalence of Definitions of Ordered Pair
 * Equality of Ordered Pairs
 * Definition:Ordered Tuple as Ordered Set


 * Definition:Cartesian Product