Question

what are the maps without scale invalid? ??​

Answer 1

Answer:

But such a “map” which lacks a scale can sometimes be called “schema” (e. g. when documenting how oil pipelines are connected), “diagram”, “pattern”, “framework”, or “structure”. Also a “plan” (e. g. for a railroad network) or an “outline” can be something which resembles a map but which has no scale.