PIN inventor: 'For 39 years I said nothing'

It is 50 years since the personal identification number (PIN) was invented.

Used by almost everyone around the world, John Goodfellow stayed quiet about his invention until someone else tried to take the credit.

"I received nothing...So I said nothing for 39 years until someone else had claimed they had done it", he told presenter John Humphrys.

(Image: Card machine prompting for PIN. Credit: Getty Images)