Hi Fauntail,
The structure Manager has an entry in its menu called Mode. Here you can access a lot of data from a given polygon or spline object.
If we select something in the scene, like five polygons of an object, that selection contains the information to reproduce the selection.
So it stores numbers, similar to the the structure manager, except, that all polygons for example are “selected” to appear, whereby the selection tag can hold all or less polygons. Of course, selections tags differ in their kind in terms of point, edge, polygon.
(UV is also in the mode, but not part of this tutorial, so it would be not the place to discuss here. But in short, as in all 3D apps, UV polygons are a representation of the object in the scene, but in a normalized space: 0-1, so the resolution of an image is not affecting the projection. Please check out the available content for UV, so we keep things organized here.)
This series was designed as a one hour introduction presentation during a hands-on class for one of the larger companies here in the US. The idea was to get them savvy with the hole production, and fast with it. Which has shown workable during these three days. So the main part here is modeling workflow.
For more information about the inner workings of C4D, in regards of the Structure manager, please check out the following:
https://help.maxon.net/us/#5872
If you really want to explore the hard core workings of Cinema 4D, there is nothing better than to check into the developer Café
http://www.plugincafe.com/forum/forum_topics.asp?FID=7
Nothing in public goes deeper than that.
Suggested tutorials (or series)
https://www.cineversity.com/vidplaylist/modeling_101_-_pat/introduction_to_polygons
https://www.cineversity.com/vidplaytut/speed-modeling_city_part_02
All the best