You mean credit card numbers don't have spaces?

Yes, it's true. Even though your account number on your credit card is shown as four groups of four digits, credit card numbers don't actually contain spaces. And surprisingly, an enormous number of online vendors are quite determined to make you realize that, under pain of not doing business with you.

You see, when you're involved in a credit card transaction, your account number is sent from the vendor's computer to the computer of a credit card clearing company as a simple 16-digit integer. Real credit card numbers, as they exist inside these various computer systems, don't contain spaces.

But since humans don't handle 16 contiguous digits very well, account numbers on cards and statements are broken down into four groups of four digits. It makes transactions involving humans proceed more smoothly and with fewer errors.

Despite the eminent sensibility of that arrangement, how many times have you gotten to the point of typing your credit card number into an online form, and it warned you to use "no spaces or dashes"? And when, out of stubbornness, you entered your number with spaces, did the web order system throw an error? Of course it did.

It turns out the genius programmers who wrote that order system were smart enough to detect that you entered a number with embedded spaces, but they weren't smart enough to programatically remove those spaces and see if the result was a 16-digit number. How dumb is that?

Actually, it's extremely dumb, even incompetent. That's because writing a computer program to remove spaces from the credit card number in an online order form is incredibly easy to do. As a computer programmer myself, I can assure you it is literally the most trivial of programming tasks. And yet, these vendors, or the programmers they hire, can't be bothered to do it. Or worse, it doesn't even occur to them.

It's even more stupid because this boneheaded intransigence is likely to cause the vendor problems. An inexperienced web user, such as an elderly person apprehensive with all this newfangled technology, might bail out of the order at the first sign of anything disturbing—such as an error message saying there's a problem with something they entered. They were, with much trepidation, on the verge of giving the vendor their money, and the vendor blew it. (See update below for more on this.)

More commonly, the requirement to enter 16 uninterrupted digits will result in a certain number of entry errors, and consequent failed transactions. When not broken up by spaces, it's harder for a human customer to visually verify the correctness of the number he just typed into the form. My old eyes have particular difficulty.

Not convinced? Consider this. Citibank has a "virtual account numbers" service that allows you to generate a credit card number for limited use—even for just a single transaction, if you want. You can, from Citibank's web site, generate a virtual account number in real time, at the moment you're completing an order with some online vendor. The virtual account number "looks" just like any other credit card number. Not surprisingly, Citibank displays that newly generated account number in an on-screen image that looks like an actual credit card that you just pulled out of your wallet. Slick. Citibank recommends that you "copy and paste" the number into your online vendor's form.

What could be easier, more natural, more error free? Except for one thing. Citibank's rendering of the account number contains, as you'd expect, spaces. But probably 70 percent of online vendors can't handle that. What a pathetic shame.

No doubt a certain number of those vendors are mom-and-pop operations that hired the kid next door to program their web site. They don't understand that the job of the user interface is to mediate between the person interacting with their web site and the considerably less user-friendly constraints of the backend computer systems that run the business. A surprising number, however, are medium to large operators that ought to "get it," but apparently don't. If your vendor makes you enter your credit number without spaces, you should take every possible opportunity to tell them how disappointed you are with their backward web site. Some may even get the message.

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Update Oct 12, 2009: An article in the New York Times highlights the peril to online retailers of allowing anything disruptive, including technical glitches, that might interfere with closing the deal. "This is revenue that people really wanted to commit to the company and were unable to do it, and it often ends up being in the millions of dollars," said one expert. Another said: "When customers are trying to purchase something, we need to do everything in our power to make sure they can do it."

Copyright (C) 2008 James Michael Brennan, All Rights Reserved