PIN code stands for Postal Index Number code. Postal Index Number (PIN) or PIN Code is a 6 digit code of Post Office numbering used by India Post. Indian Postal Service introduced the 6 Digit Zip code or PIN Code on 15th August 1972, inorder to make the process of delivering letters and parcels more efficient.
As stated above, PIN code is a 6 Digit Number. Each Digit number has a Specific meaning. First digit reflects region in India, second the sub-region, third the sorting district, and last three represent the post office code. Thus the first 3 digits collectively indicates the postal district while the last 3 digits designates the specific post office within the district. In India there are 9 PIN regions, out of which 8 belongs to geographical regions, and the digit 9 is reserved for the army Postal service.