Kolkata along with its metropolitan area, is the main financial and commercial region of East India.
Kolkata metropolitan region is one of the seven metro areas in India with a high number of commercial spaces and offices.
Bagh, Park Street and PBD areas like Salt Lake Sector-V and New Town CBD.
Kolkata being the "IT hub of East India", most of the IT and tech parks are located in Salt Lake (officially Bidhannagar) and New Town.
Salt Lake Sector-V is the first and prime IT hub of the metropolitan area.