-- chapter1. //7.
-- Le`s Make a Gmae Using Molehill
* Vector3D: containing an x, y, and z component
* Normal: a Vector3D that has a length of one
* Matrix: a 4x4 group of vectors with position, rotation, and scale
* Vertex: a point in space that is the corner of a polygon
* Polygon: a shape defined by multiple vertex coordinates
* Mesh: a group of polygons (polies) that make up a model
* Texture: a bitmap image that is like wallpaper for a mesh
* Shader: the combined result of a vertex program and a fragment program
* Vertex program: commands affecting the shape of a mesh
* Fragment program: commands affecting the look of a mesh