A Quad Mesh is similar to a Triangle Strip Set, but uses an array of quadrilaterals to define the shape instead of triangles. There are a number of different kinds of properties that you can apply, each with a different node class. Whereas shape nodes tell the rendering engine to draw the shape in question, property nodes affect the state of the rendering, changing the way that subsequent shapes will be drawn. Thus, a property must always come before the shapes it is to affect. An SoMaterial node affects subsequent objects in the scene.
Phong lighting is the default, and usually looks much more natural.
An SoEnvironment allows you to specify the atmosphere of the scene. An SoShapeHints node allows you to specify several characteristics of the subsequent shapes, which can speed up rendering of the scene. An SoComplexity node allows you to specify how much you want the renderer to subdivide subsequent objects into polygons. If you specify less subdivision, rendering in generally faster. Meters are the default unit.