VRML includes a way of defining new shapes (called nodes) from within itself. So one can, for example, build a model of a car or plane or a lamp which let's itself to be turned on and off - and yet use them just as if they were basic VRML primitives like Box, Cylinder, Cone, etc.
The organisation of the library: The library contains prototype definitions of various pieces of furniture, most of which there are also several modifications. The distinct "types" of furntiture in the library are:
Licencing. The library is going to be licenced under a licence similar to the BSD licence, or in other words - can be used, modified and distributed freely.