How come to know that this area of earth is India ,China or Japan etc?

Question

How it has been discovered that this area of earth has been called as India,China or USA etc.

Answer 1

When you look at them from space you can see their names written on them, just like a map.  

The oceans' names are written with little black floats but they're so far offshore you can't see them from the beach.

Answer 2

Those are just the names of regions, for communication purposes, in reality there is no name, it's just categories we use for sorting, to be able to control an area easier because it's smaller in size.

But we don't seem to be doing a very good job.