Why an ATM PIN Has Four Digits
In case you were wondering:
Mr Shepherd-Barron came up with the idea when he realised that he could remember his six-figure army number. But he decided to check that with his wife, Caroline.
"Over the kitchen table, she said she could only remember four figures, so because of her, four figures became the world standard," he laughs.
Posted on July 4, 2007 at 8:52 AM • 66 Comments