How many region are in US?

Answer 1

That's impossible to answer. Regions are not hard lines on a map. It depends on how you define them.

Regions can be as loosely defined as north, south, east, west, and central (which would be true for any country). There are big regions like the coasts, the mountains, and the plains. The U.S. can also be broken down finely into such regions as Pacific Northwest, Great Lakes, and New England--and there are many of those. Even individual cities can have sections that are very different from one another.

In other words, it's pretty arbitrary. Think of any system you want (political, agricultural, topological, economic, etc.) and you can probably divide the country up into regions based on it.