A PIN code (Postal Index Number) is a six-digit code used by India Post, the country's postal service, to identify the location of a specific post office where mail or parcels are to be delivered. The PIN code system was introduced in India in 1972, and it is used in all parts of the country.
Each PIN code identifies a specific geographic region, including a particular district, state, and post office. The first digit of the PIN code represents the region or zone, the second digit represents the sub-region or circle, and the third digit represents the district. The last three digits represent the specific post office within that district.