Beth,
Only materials in a "virtual" sense. I do 3D presentation graphics for concept visualization, design analysis etc. It's all virtual, nothing is real...but the software is so incredible advanced that you can simulate just about any material, including many of it's physical properties in case you need to animate it in a movie and have it behave as it would in real life.
The reflections are taken care of by a process called "ray-tracing" where the computer calculates the actual path of virtual photos from light sources, to object, to the next object, back and forth etc. Very CPU intensive as you might imagine. But you can control the "depth" of the reflections....meaning how many times an object is reflected back and forth to other objects.
"Material" is the term used for an extensive set of color/texture/bump/reflectivity parameters that imitate the real material when applied to an object.
This materials is made with a base color, then an overlay color, then different colors for reflections, and indirect light (irridesence), and finally a metal flake added with it's own color and reflection parameters.
I'm not happy with the indirect lighting effect...too white/washed out looking. Note the right side of the red square...looks too rough, not glossy enough.
JohnnyB