These subroutines tell you whether a credit card number is self-consistent --
whether the last digit of the number is a valid checksum for the preceding
digits.  If you additionally want to process the credit card electronically,
see Business::OnlinePayment <>

Original author is Jon Orwant <>, The Perl Journal and MIT
Media Lab 

Current maintainer is Ivan Kohler <>.
Please don't bother Jon with emails about this module.

Lee Lawrence <>, Neale Banks <> and
Max Becker <> contributed support for additional card
types.  Lee also contributed a working