Nice history lesson that you've written for absolutely no reason, but we still don't know what there is other than rural and urban. Pointlessly pointing out obvious things like that there can be suburbs within urban areas, like there can be hamlets in rural areas, does not answer the question or serve any purpose whatsoever.
> Nice history lesson that you've written for absolutely no reason…
This you?
> …originally referring to the portion of an urban area found outside of the wall.
The physical walls aren't often found anymore, but the term still refers to an urban area that surrounds where a wall might have been placed historically.