By Mark Ward
Technology correspondent, BBC News website
The 100th anniversary of the birth of programming language pioneer Grace Hopper was celebrated on 9 December. Widely credited as being the "mother" of the Cobol computer language her work was hugely influential.
Dr Hopper regularly lectured in her dress uniform
Even now if you take cash from an ATM, renew the MoT on your car or file your taxes, a Cobol program will handle some of the work involved.
It is a state of affairs that undermines the assertion that the only constant in the world of hi-tech is change.
The implication is that the relentless pace of technology development means anything more than a few months old is thrown out along with the empty pizza boxes.
A look below the surface of the computer world uncovers some very old technology - such as the Cobol programming language. The Common Business Oriented Language was created in 1959 and, though it is no longer taught in schools and universities, you still bump up against it every day.
"Industry analysis puts the Cobol footprint at something of the order of two hundred billion lines of code," said Julian Dobbins, a spokesman for Micro Focus - one of the few companies that still works with Cobol.
In its heyday Cobol was used to write programs that ran on the enormously powerful mainframe computers used by the biggest businesses.
"For 40 years it was the primary commercial programming language," said Dr Roger Johnson, chair of the computer history group of the British Computer Society.
Dr Hopper, who had a PhD in mathematics, gained her familiarity with computers thanks to the US Navy. She joined the US Naval Reserve in 1943 and was put to work on the Mark 1 Calculator - one of the first digital computers.
She went on to work on the Univac - the first commercial computer in the US - and it was at this time she did the pioneering work that led to Cobol.
Her inspiration was to create a computer language that read more like real English rather than the tortuous machine code used by many other programming languages of the time.
"At an early date the US government said all of its data processing applications were to be written in Cobol," said Dr Johnson. "So every computer maker had to have it on their machine if they wanted to sell it to the US government.
"It was only the coming of the internet and e-commerce-type applications that finally displaced it," added Dr Johnson.
Dr Hopper handed out foot-long wires to illustrate nanoseconds
Much of the work done to combat the millennium bug involved re-writing Cobol applications which only used two digits to represent dates. The fear was that the advent of the millennium would make these programs think it was 1900 rather than 2000.
It was a testament, said Dr Johnson, to how the language outlived the lifespan its creators thought it would enjoy.
"If she were around to celebrate her 100th birthday, she would be impressed by the way computing has moved on and would be proud of the fact that a language she helped shape is still helping to drive that world," said Mr Dobbins.
Dr Hopper maintained her connections with both computers and the navy throughout her life.
Despite retiring from the Naval Reserve as a Commander in 1966, she was recalled to active duty and spent much of her time travelling the world lecturing on her life and the early days of computers. She ended her time in the navy with the rank of rear-admiral. She died in 1992.
Dr Johnson heard her lecture on several occasions and. He recalled that she was very entertaining, not least because she was always in naval uniform when talking.
One of the aids she used during lectures were foot-long lengths of wire which she described as "nanoseconds" as that is the distance light travels in a nanosecond - one-billionth of a second.
Despite the entertainment value, Dr Johnson, suspected there was a steely side to Dr Hopper - perhaps because of the time she spent in the navy.
"On the surface she was quite homely but I suspect she did not suffer fools gladly," he said.