In the Blender UI, what is the difference between the Properties region (the thing that can be opened with N) and the Properties editor (the thing at the very right)?
What do they apply to (e.g. current selection/viewport/globally) and what kind of settings can I expect in each of them? In other words, if I were a developer adding a feature, how would I decide whether to put the UI in the Properties panel or the Properties window?