Turing pioneered modern computing and was instrumental in breaking the German Naval Enigma cipher in 1942, at Bletchley Park.
His life was cut short, however, after he died at just 41-year-old having faced persecution for his sexuality.
Who was Alan Turing?
Alan Turing was a wartime hero, considered to be the father of computer science.
Born on June 23, 1912, Turing studied mathematics at King’s College, Cambridge, gaining a first-class honours degree in 1934. He was elected a Fellow of the College.
In 1936, his work on Computable Numbers is seen as giving birth to the idea of how computers could operate.
But it was during the Second World War that his genius came to save the lives of millions.
His role in cracking the Enigma code is widely seen as helping to bring WWII to an end, at least two years earlier than it might otherwise done.
He played a pivotal role in decoding the cypher, used by German forces and thought to be unbreakable, the legacy of this work has a lasting impact on the way we live today.
Why was he convicted?
In January 1952, Turing was prosecuted for "indecency" over his relationship with another man in Manchester.
At the time, it was a criminal offence in the UK for people to engage in homosexual acts - a law that remained in place until 1967.
He was given a choice between imprisonment or probation on condition of undergoing "chemical castration" - he chose the latter.
The computer scientist was also banned from working at GCHQ, the organisation in which he had been instrumental in bringing an end to the war.
Court papers from the time note his sentence as being "placed on probation for twelve months" and ordering him to "submit for treatment by a duly qualified medical practitioner at Manchester Royal Infirmary".
Just two years later Turing took his own life aged just 41.
Why is Turing being printed on a £50 note significant?
The appearance of Turing's image on a British bank note is a major step in the fight for recognition of his work.
Campaigners have long demanded he be celebrated for his achievements.
It took decades of campaigning for Turing, and other men convicted under laws that banned homosexuality, to receive an apology.
The Queen posthumously pardoned Turing in 2013. The then-Justice Secretary, Chris Grayling, said it was a "fitting tribute to an exceptional man".
Aside from the posthumous royal pardon, Turing has received several formal apologies.
In September 2009, then-Prime Minister Gordon Brown apologised on behalf of the government for Turing's prosecution.
"We're sorry, you deserved so much better," he said in an official statement posted on the Downing Street website.
Stephen Hawking, who was also shortlisted to become a face on the £50 note, urged the then prime minister to make the apology.
In April 2016, GCHQ boss Robert Hannigan formally apologised on behalf of the organisation from which he was expelled following his conviction.
He said: "The fact that it was common practice for decades reflected the intolerance of the times and the pressures of the cold war, but it does not make it any less wrong and we should apologise for it.
"Their suffering was our loss and it was the nation’s loss too because we cannot know what [those] who were dismissed would have gone on to do and achieve. We did not learn our lesson from Turing."