John Shepherd-Barron, the man credited with inventing the world's first cash machine, has died in hospital in Scotland at the age of 84.
Shepherd-Barron, who worked for a printing firm, reputedly came up with the idea for a free-standing cash dispensing device during a eureka moment in the bath.
In an interview with the BBC in 2007, Shepherd-Barron said: "It struck me there must be a way I could get my own money, anywhere in the world or the UK.
"I hit upon the idea of a chocolate bar dispenser, but replacing chocolate with cash."
The first machine was commissioned by Barclays and installed at a branch in Enfield in 1967.
In the absence of plastic cards, the first machines accepted special paper cheques impregnated with carbon 14 and would dispense up to a maximum £10 per transaction.
Shepherd-Barron credited his wife with the idea for a four-digit PIN code after first toying with the use of a six-digit security code. He told the BBC: "Over the kitchen table, she said she could only remember four figures, so because of her, four figures became the world standard."
James Goodfellow, of Paisley, Renfrewshire, was credited with being the inventor of the PIN and awarded an OBE in 2006, 40-years after he first applied for a patent. He devised a method for PIN-entry code keying in the 1960s.
Paul Volcker, the former chairman of the Federal Reserve recently described the cash machine as the last truly great innovation in financial services.