Luhn algorithm

The Luhn algorithm, also known as the "modulus 10" or "mod 10" algorithm, is a simple checksum formula used to validate various identification numbers, such as credit card numbers. It was developed by IBM scientist Hans Peter Luhn in 1954. ### Steps of the Luhn Algorithm: 1. **Starting from the rightmost digit (the check digit) and moving left**, double the value of every second digit.