C validating a credit card
The main purpose of the Luhn Check Digit Algorithm is to catch data entry errors, but it does double duty here as a weak security tool.
To be completely clear and spell this out, these fake credit card numbers should not be used to try and purchase stuff.
They merely respect guidelines of a valid credit card number.
The issuer identification number also known as the bank identification number (BIN) is the first six digits of the credit card number.
These identify the institution that issued the credit card to the card holder. Afterwards comes the account number, digit 7 to last minus one.
A valid credit card number (also known as Primary Account Number - PAN) has several fields and each of them has a meaning.
For the technically inclined, this number complies to the ISO/IEC 7812 numbering standard.
If it gives you a last digit different from the one you have, you have an invalid credit card number.
First of all not every 16 digit is CC number, but only by number you can know the issuer.
The following link specifies all group of digits and their purpose: Cracking the credit card digits Do you need a currency converter for your online purchases?Tags: Adult Dating, affair dating, sex dating