Credit Card Processing (Was: Digest, Vol 57, Issue 4)

Ovid publiustemp-londonpm at
Sat Jul 10 16:18:03 BST 2010

----- Original Message ----
> From: Smylers <Smylers at>

> > **  IIRC only the digits from the postcode are used. I'm guessing that
> >     the spec was made in the USA, where ZIPs are only digits.
> My guess  was this was so that merchants taking telephone orders can
> punch them into a  PDQ terminal which only has a numeric keypad. (But I
> have no evidence for  that.)

A friend of mine who maintains a lot of credit card processing software states 
that only numbers are used because people mistype them less often than the 
Buy the book -
Tech blog -
Twitter -
Official Perl 6 Wiki -

More information about the mailing list