If you are interested in the when and why for configurations, I give some examples below.
When a few parts or assemblies are so alike it is easier to put them on one drawing, we model the variations as configurations. Each configuration gets a dash number. Drawing number + dash number specifies one part or assembly. We use these configurations for both drawing views and as components.
A drawing view may need some special modification to the model for clarity, such as a complex section or arrangement of components. We use these only for drawing views.
A component may be modified in the assembly process, and we model these in a configuration. Such operations include cut to length, match drilled, bent to fit, poured into a vessel, painted. We use these only as assembly components and only for features specified in the assembly drawing, not in the component's own drawing.
In higher level assemblies, a model with too many features may slow performance unacceptably. We use simplified configurations for select components in big assemblies.
There are many other uses. These are just the ones we formally define and name.
Thank you very much Dwight Livingston
A couple of our uses of configurations:
1. Castings, as cast and as machined versions.
2. Fasteners, different sizes as configurations.
3. Tubes, different lengths as configurations.