An Introduction to 3D: Recreating the World Inside Your Computer, or Not - Blender Foundations: The Essential Guide to Learning Blender 2.6 - page 4

Figure 1.2 Vertex, edge, and face.
Surfacing
Surfacing refers to the way that surfaces look. Once again, we can examine the real world to learn a few
things. We know what wood looks like. However, it looks different when it's part of a tree, freshly cut,
or stained and finished in a piece of furniture. Each of these surfaces have different visual properties. A
tree is rough—the bark is generally a brownish gray, rough, occasionally covered with moss or lichen. Cut
wood is often light (excepting things like walnut, of course) with a pattern of concentric circles. It is
generally smooth, although if you look closely you can see a pattern of grain. Finished wood that is part
of a piece of furniture can be many colors; for example, it can be extremely smooth and highly reflective,
in the case of a grand piano.
So, while models tell us what forms we are looking at, surfacing gives us the additional clues we need to
understand what the forms are made of ( Figure 1.6 ).