In India, PIN is an acronym of Postal Index Number. Not to be confused with the personal identification number referred to as a 'PIN' in other countries, PIN codes in India are six digits long and communicate postal/address information. There are currently nine coastal zones in India, comprising eight regional zones and one functional zone reserved for military use.
Every PIN code features the same format, with the first digit communicating the respective region, the second indicating the sub-region and the third narrowing things further to the specific district of the sub-region. The remaining three digits of the PIN code detail the individual postal address within the respective district.
This standardised postal address numbering system used by Indian Postal Services was introduced to simplify and accelerate everyday mail delivery processes. Rolled out nationwide in August 1972, the system is essentially quite similar to the Zip Codes of the United States or the Postcodes of the United Kingdom.