About Pin Code
Indian Postal department use Postal Index Number(PIN) or Pincode for post office numbering. PIN code is a 6 digit code is used to find out delivery Post Offices in India. The PIN codes are divided in 9 zones. The first digit represents the region. The second digits represents the sub-region, and the third digit represents the district of that region.
For more information and history of Postal Code System in India, visit to Wikipedia link.