ATM celebrates 40th birthday

The first 'cash point' automated teller machine (ATM) was installed in Britain 40 years ago today.

The machine, installed by Barclays at its Enfield branch in London, did not use a plastic card to access accounts, but instead used radioactive cheques impregnated with a small amount of Carbon 14.

The first customer was Reg Varney, from the television show On the buses, who withdrew the maximum amount then allowed of £10.

"That was regarded then as quite enough for a wild weekend," ATM inventor John Shepherd-Barron told the BBC.

"It struck me that there must be a way I could get my own money, anywhere in the world or the UK. I hit on the idea of a chocolate bar dispenser, but replacing chocolate with cash."

Shepherd-Barron said that, although the cheques were radioactive. he had calculated that people would have to eat 136,000 of them to suffer any harm.

He decided on using a Pin for security after realising that he could easily remember his six-digit army number.

But tests conducted on his wife found that the most she could reliably remember was a four-digit number, so Shepherd-Barron standardised on that.

The ATM Industry Association estimates that there are over 1.5 million ATMs in operation around the world today, including a terminal at McMurdo Station in Antarctica.

Shepherd-Barron was awarded an OBE for his invention in 2005.