Road is a system. It is smooth surface designed for ease of driving and walking. And it is of course the universal network as a whole open to anyone. Combination of civil engineering work and free access is road.
Yes. But when you drive some remote lonely road at midnight, you are not aware of the system, but the outline is what you really want. Guardrail and solid white line stretching in the dark which gives you the clear-cut image of the safe rout you should keep. Distinction is more important than the paved surface itself.
Like cartoons and animations and drawings, outline is the key for our recognition. The definition is what we want, because it assures that the safety is really there. Road is elaborately designed so that it can definitely exist in our mind.
