On a comic's Info page, what does the switch do?

On a comic's Info page, what does the toggle switch between “Number” and “Of” do exactly? It seems redundant to me. It's also possible that I'm using it wrong, though, which is why I'm here asking.

Thank you in advance.

You can ignore that, I’ll remove it in a future info view overhaul. Numbers are already strings in YACReaderLibrary so you can add issues in between, e.g. 3, 3.1, 3.2, 4. Before that the switch was used for 3 and 3bis.