An _n-tuple_ or simple _tuple_ or _list_ is an [ordered set](Ordering.md#Ordered%20sets) of finite length $n.$ These elements may be composed of any [set](Sets.md) of [mathematical objects](Mathematical%20object.md). e.g. numbers, any number of mathematical abstract objects, other n-tuples, etc. We may write out an [n-tuple](n-tuples.md) as $(x_1,... ,x_n)$ where we use paranthesis instead of braces, which are used to write [sets.](Sets.md) A [tuple](n-tuples.md) containing $0$ elements is still considered a tuple and is referred to as an _empty tuple,_ which may be expressed as $().$ When we know the value of $n$ in an [n-tuple](n-tuples.md) it may be referred to as an _[ordered pair](Ordered%20pairs.md)_ or _double_ for $n=2,$ a _triple_ when $n=3,$ _quadruple_ when $n=4,$ _quintuple,_ when $n=5,$ and so on. %%A list is a term used in computer science as well to refer to an ordered datastructure. We may need to define list for the computer science context but from what I can understand a list in computer science is the same as a tuple.%% ^f168da # Properties of n-tuples #MathematicalFoundations/SetTheory