# Definition:Array/Square

## Definition

An array whose dimensions are equal is called a square array.

That is, a square array is an array which has the same number of rows as it has columns.

A square array $\left[{a}\right]_{n n}$ is usually denoted $\left[{a}\right]_n$.

### Order of Square Array

Let $\mathbf A$ be an $n \times n$ square array.

That is, let $\mathbf A$ have $n$ rows (and by definition $n$ columns).

Then the order of $\mathbf A$ is defined as being $n$.