Youonyourfinance on Instagram: "Do Follow for more Financial knowledge… A PIN code stands for Postal Index Number, which is a six-digit numeric code used in the Indian postal system by India Post. It was introduced on August 15, 1972, by Shriram Bhikaji Velankar to simplify the manual sorting and delivery of mail, avoiding confusion caused by similar place names, different languages, and incorrect addresses. The structure of the PIN code is as follows: the first digit indicates the postal zone,