> > How about when they ask you what type of credit card you are using when > in actuality, the first digit of the number denotes the card type? > Norm >
redundancy is an important aspect of verifying user input. Something can be valid but still wrong, so an element of redundancy helps to detect this. It's particularly important in secure applications. A check digit is a form of redundancy designed with this in mind, but there's a 1 in 10 chance that you can get the right one accidentally. B -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
