Postal Code, also known as a PIN code (Postal Index Number), is a six-digit code used in the Indian Postal Code system by India Post. Postal Code was introduced on August 15, 1972 by Shriram Bhikaji Velankar, an additional secretary in the Government of India’s Ministry of Communications. Postal Index Number Code simplifies mail sorting and delivery. Each digit in the Postal Code (PIN code) has a specific meaning: the 1st indicates the Zone, the 2nd the Sub-Zone, and the 3rd, combined with the first two, identifies the sorting District within that Zone. The final 3 digits correspond to individual Post Offices within the sorting District. India has 9 PIN zones.