LONDON: The Bank of England on Thursday unveiled the design of the new GBP 50 banknote, which features British scientist and World War II codebreaker Alan Turing.
The polymer note, which includes an image of Turing and other related imagery, will be issued for the first time on June 23, coinciding with what would have been the mathematician's 109th birthday.
"There's something of the character of a nation in its money, and we are right to consider and celebrate the people on our banknotes. So I'm delighted that our new GBP 50 features one of Britain's most important scientists, Alan Turing," said Bank of England Governor Andrew Bailey.
"Turing is best known for his codebreaking work at Bletchley Park, which helped end the Second World War. However, in addition he was a leading mathematician, developmental biologist, and a pioneer in the field of computer science," he said.
"He was also gay, and was treated appallingly as a result. By placing him on our new polymer GBP 50 banknote, we are celebrating his achievements, and the values he symbolises," he added.
Turing was prosecuted for homosexuality in 1952 and died of cyanide poisoning two years later.
In 2009, then British Prime Minister Gordon Brown made an official retrospective public apology for his treatment at the hands of the British government at the time.
Jeremy Fleming, Director of GCHQ -- the Government Communications Headquarters which houses the modern-day codebreakers, said Alan Turing's appearance on the GBP 50 note is a landmark moment in UK history.
He said: "Not only is it a celebration of his scientific genius which helped to shorten the war and influence the technology we still use today, it also confirms his status as one of the most iconic LGBT+ figures in the world.
"Turing was embraced for his brilliance and persecuted for being gay. His legacy is a reminder of the value of embracing all aspects of diversity, but also the work we still need to do to become truly inclusive."
The new note will feature the signature of Sarah John, the Bank's Chief Cashier, who said it completes the set of polymer banknotes.
"These are much harder to counterfeit, and with its security features the new GBP 50 is part of our most secure series of banknotes yet. These security features are common across all our banknotes, so if you can check one, you can check them all," she said.
The new polymer GBP 50 note's advanced security features incorporate two windows and a two-colour foil, making it very difficult to counterfeit.
There is also a hologram image which changes between the words 'Fifty' and 'Pounds' when tilting the note from side to side.
According to the Bank of England, one of the benefits shared by all our polymer banknotes is that they last longer than paper notes and they stay in better condition during their use.
The new note, like the newer GBP 10 and 20 notes, also contain a tactile feature to help vision impaired people identify the denomination.
The new GBP 50 note includes a photo of Turing taken in 1951 by Elliott & Fry, which is part of the Photographs Collection at the National Portrait Gallery in London.
It also has a table and mathematical formulae from Turing's seminal 1936 paper "On Computable Numbers, with an application to the Entscheidungsproblem' Proceedings of the London Mathematical Society."
This paper is widely recognised as being foundational for computer science.
It sought to establish whether there could be a definitive method by which any theorem could be assessed as provable or not using a universal machine.
It introduced the concept of a Turing machine as a thought experiment of how computers could operate.
Besides his signature, there is also a quote from Alan Turing, from an interview to 'The Times' newspaper on 11 June 1949: "This is only a foretaste of what is to come, and only the shadow of what is going to be".