Matrix Transformation
Matrix transformations are equations of the form:
$$ T(x) = Ax $$
Where $A$ is a matrix. The domain of the transformation is the size of the vector that is inputted into the transformation, while the codomain is the size of the vector that transformation outputs:
In the case of a matrice like:
$$ \begin{bmatrix} 1 & 4 & 3 \\2 & 7 & 1 \end{bmatrix} $$
The domain is its length, while the codomain is its height. (Due to the properties of Matrix-Vector Product). While its range is the Vector Span of its column.