Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. He was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science.
Bletchley Park is an English country house and estate in Bletchley, Milton Keynes (Buckinghamshire), that became the principal centre of Allied code-breaking during the Second World War. The mansion was constructed during the years following 1883 for the financier and politician Herbert Leon in the Victorian Gothic, Tudor and Dutch Baroque styles, on the site of older buildings of the same name.
Colossus was a set of computers developed by British codebreakers in the years 1943–1945 to help in the cryptanalysis of the Lorenz cipher. Colossus used thermionic valves to perform Boolean and counting operations. Colossus is thus regarded as the world's first programmable, electronic, digital computer, although it was programmed by switches and plugs and not by a stored program.
The known-plaintext attack (KPA) is an attack model for cryptanalysis where the attacker has access to both the plaintext and its encrypted version (ciphertext). These can be used to reveal secret keys and code books. The term "crib" originated at Bletchley Park, the British World War II decryption operation, where it was defined as:
A plain language passage of any length, usually obtained by solving one or more cipher or code messages, and occurring or believed likely to occur in a different cipher or code message, which it may provide a means of solving.
Thomas Harold Flowers MBE was an English engineer with the British General Post Office. During World War II, Flowers designed and built Colossus, the world's first programmable electronic computer, to help decipher encrypted German messages.
Sir Edward Wilfred Harry Travis was a British cryptographer and intelligence officer, becoming the operational head of Bletchley Park during World War II, and later the head of GCHQ.
Sir Francis Harry Hinsley, was an English intelligence officer and historian. He worked at Bletchley Park during the Second World War and wrote widely on the history of international relations and British Intelligence during the Second World War. He was known as Harry Hinsley.
William Gordon Welchman OBE was a British mathematician. During World War II, he worked at Britain's secret decryption centre at Bletchley Park, where he was one of the most important contributors. In 1948, after the war, he moved to the US, and later worked on the design of military communications systems.
Commander Alexander "Alastair" Guthrie Denniston was a Scottish codebreaker in Room 40, deputy head of the Government Code and Cypher School (GC&CS) and hockey player. Denniston was appointed operational head of GC&CS in 1919 and remained so until February 1942.
Hut 6 was a wartime section of the Government Code and Cypher School (GC&CS) at Bletchley Park, Buckinghamshire, Britain, tasked with the solution of German Army and Air Force Enigma machine cyphers. Hut 8, by contrast, attacked Naval Enigma. Hut 6 was established at the initiative of Gordon Welchman, and was run initially by Welchman and fellow Cambridge mathematician John Jeffreys.
John Robert Fisher Jeffreys was a British mathematician and World War II codebreaker.
Hut 3 was a section of the Government Code and Cypher School (GC&CS) at Bletchley Park during World War II. It retained the name for its functions when it moved into Block D. It produced military intelligence codenamed Ultra from the decrypts of Enigma, Tunny and multiple other sources. Hut 3 thus became an intelligence agency in its own right, providing information of great strategic value, but rarely of operational use. Group Captain Eric Malcolm Jones led this activity from 1943 and after the war became deputy director, and in 1952 director of GCHQ. In July 1945, General Dwight D. Eisenhower Supreme Commander of Allied forces wrote to Sir Stewart Menzies, Chief of the British Secret Intelligence Service (MI6) saying inter alia:
"The intelligence that has emanated from you before and during this campaign has been of priceless value to me. It has simplified my task as commander enormously. It has saved thousands of British and American lives and, in no small way, has contributed to the speed with which the enemy was routed and eventually forced to surrender."
The Imitation Game is a 2014 American period biographical thriller film directed by Morten Tyldum and written by Graham Moore, based on the 1983 biography Alan Turing: The Enigma by Andrew Hodges.
Joan Elisabeth Lowther Murray, MBE was an English cryptanalyst and numismatist who worked as a code-breaker at Bletchley Park during the Second World War. Although she did not personally seek the spotlight, her role in the Enigma project that decrypted the German secret communications earned her awards and citations, such as appointment as a Member of the Order of the British Empire (MBE), in 1946.
The Turing Guide, written by Jack Copeland, Jonathan Bowen, Mark Sprevak, Robin Wilson, and others and published in 2017, is a book about the work and life of the British mathematician, philosopher, and early computer scientist, Alan Turing (1912–1954).
Sir John Dermot Turing, 12th Baronet is a British solicitor and author.
Simon Greenish is a British Chartered Civil Engineer and museum director.
A statue of Alan Turing, created in slate by Stephen Kettle in 2007, is located at Bletchley Park in England as part of an exhibition that honours Turing (1912–1954). It was commissioned by the American businessman and philanthropist Sidney Frank (1919–2006).
Action This Day was a 1941 memorandum sent to Winston Churchill personally, to advise Churchill that the Bletchley Park (BP) codebreaking establishment was short of staff in some critical areas. Their requirements were small, but as a small organisation their management did not have priority. Four senior heads of sections ("Huts") and their deputies wrote to Churchill, who had visited "BP" on 6 September 1941, where he made a speech saying he appreciated their work.
