Theoretically, India is divided into five regions: North, North-East, South, West, and East. The diversity within these regions is a lot harder to identify.
Each harbours tremendous variety in beliefs, ideologies, clothing, cuisine, rituals, festivals and demographics. This impacts perception and understanding, which means each community must be approached differently.
This is one of the first rules of doing business in India: what you say is just as important as where you say it.