1. Let's start by stating the problem: We want to understand what a matrix is and see an example. 2. A matrix is a rectangular array of numbers arranged in rows and columns. For example, a matrix $A$ with 2 rows and 3 columns looks like this: $$A = \begin{bmatrix} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \end{bmatrix}$$ 3. Each element $a_{ij}$ represents the number in the $i$-th row and $j$-th column. 4. Let's take a concrete example: $$A = \begin{bmatrix} 1 & 2 & 3 \\ 4 & 5 & 6 \end{bmatrix}$$ 5. This matrix has 2 rows and 3 columns, and the elements are the numbers shown. 6. Matrices are used in many areas such as solving systems of equations, transformations in geometry, and more. Final answer: The example matrix is $$\boxed{\begin{bmatrix} 1 & 2 & 3 \\ 4 & 5 & 6 \end{bmatrix}}$$