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As a credit card holder, have you ever wondered what those set of numbers embossed on the front part of your credit card mean? This 16-digit number is referred to as your Credit Card Number and is unique for every individual.
Typically, credit cards have the 16 digits on the front of the card. These digits are exclusive for every card holder and denote the individual account number for the card. These sixteen digit numbers and not randomly generated and follow a pattern.
There is a lot more information packed into those sets of numbers, and the first few digits helps identify the kind of card you are holding. If you have your credit card handy, then you can pull it out so that you follow the meaning of these numbers.
The first digit in the number denotes the type of card you are holding. This number is always a 3, 4, 5, or 6 (in case of international credit card). Following is a breakdown on which number denotes what:
3 - Travel or entertainment card
4 - Visa Card
5 - MasterCard
6 - Discover
In a typical sixteen-digit credit card number, the first fifteen digits are determined by the issuing bank, while the last number is mathematically determined to rule out any error. To elaborate, in your credit card number, the 2nd through to 6th digits denote the bank number, and the 7th-15th numbers denotes your account number. The remaining digit is known as the check digit. This number is used to determine the authenticity of the overall number and to rule out any invalid numbers. The check digit is mathematically determined based on all the other digits.
Importance of Check Digit
When the bank processes a payment, you need to quote your credit card number. Credit card numbers are often typed in, input by a third person, transferred or quoted. All these kinds of communication can result in error. A check digit is included to try and minimize these kinds of human errors. The check digit also serves the purpose of protection - it provides a small amount of protection from poorly educated hackers who might attempt to randomly estimate and generate credit card numbers by guessing the numbers.
How Are Credit Card Numbers Generated?
Credit card numbers are generated by using an algorithm known as the Luhn algorithm. A credit card number is valid if, and only if, it satisfies the Luhn Check. To put it in simple terms, it is a simple mathematical test that involves manipulating and adding the credit card number. Only then, a credit card number is deemed valid.