Basically, a 3D model, or 3D mesh, is constituted by its Geometry and its Materials.
The Geometry is a mathematical function that defines the shape of a 3D object through polygons or triangles.
The Materials are layers on top of a 3D object that define the way it will look once rendered. They behave pretty much the same way as their physical counterparts do in the real world: the way light interacts with their surfaces, the nuances of color they have, their texture, transparency, and reflectance.
A material can include the following textures. Each one of them can be edited to achieve the desired look of a 3D object:
- Color / Diffuse / Albedo: the color of the material
- Normal: used to simulate surface details
- Ambient Occlusion: how much the ambient light affects the base color
- Roughness: how polished or rough the material is
- Metalness: how metallic or non-metallic the material is