Matrices in computer graphics are the transformations given to each coordinate in the model. Each Matrix is a combination of multiple transformations to apply to a coordinate (a point in 3-space).
Building a transformation is based from one of three transform types: Translate, Rotate and Scale.
A translation matrix is something like:
And a scale matrix:
Rotation matrices look like:
To combine any of these matrices you just multiply them together. To apply the transformation to a vertex just multiply to the vertex (as seen in the translation diagram).
