Hey Sachin

Please elaborate which PIN you have a query about. There are various characteristics and elements named PIN.

1. PIN (Postal Index Number) : This is a 6 digit long code that indicates your post office numbering and signifies the region you lie in India
2. PIN (Personal Identification Number) : It is a type of security code that allows to secure your devices or data and only allows only the authorized person which are identified by PIN. Example: Phone PIN, ATM PIN
3. PIN: It is also an instrument used to combine two more objects through a pointed needle.

For Personal Identification Number: When you set up a PIN and later access that system, the system will show you Keypad to enter the PIN to be able to access that system/file. When you enter the PIN, the system checks it with the one assigned by the user, if it is correct, the access would be allowed. If it is not matched then it will show, "Wrong" and will let you put another PIN. it is a very efficient way to secure data and devices .