

Cracking The Credit Card Code - japaget
http://www.mint.com/blog/trends/credit-card-code-01202011/

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dlsspy
I wrote code for this ten or so years ago. I don't say that to brag, but to
express my annoyance at every credit card form I encounter on the internet.
Why do you ask me for my number _and_ what type of card I've got?

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dminor
Well, people are conditioned to expect it now, so taking it out could
potentially have adverse effects. Might make an interesting A/B test.

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eru
How about just putting the form for the number first, and the let the drop-
down menu for the type of card automatically select the right type---while
still allowing user interaction.

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dlsspy
The worst ones do half of each -- they tell you that you entered a Visa and
didn't press the Visa button and ask you to go back and press the Visa button.
Thanks.

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joblessjunkie
<http://en.wikipedia.org/wiki/Luhn_algorithm>

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anonymous246
This is a bad submission: it's trivial to get this info. Flagging. Sorry I'm
also posting this comment. Top hit for "credit card number format" has all
this info. <http://www.merriampark.com/anatomycc.htm>

