Alan Turing (b. 23 June 1912 –, d. 7 June 1954), was a British mathematician, logician, cryptanalyst, and computer scientist. He is known for formalisation of the concepts of "algorithm" and "computation" with the Turing machine, which played a significant role in the creation of the modern computer. Turing is widely considered to be the father of computer science and artificial intelligence.
He was a homosexual and in his time, homosexuality was illegal in England. He was treated with female hormones (chemical castration) and was treated in an appalling way. He died in 1954 by biting an apple with cyanide. In 2009, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for "the appalling way he was treated". June 23, 2012 was the birth centenary of this legendary mathematical and computing genius.
Captcha & Allan Turing
Every now and then, random computer and web applications ask us to prove that we are indeed human.
This popular and ubiquitous security test, widely known as Captcha, requires us to enter characters that we are shown to convince the system that we’re not code. Technologists know this as a reverse Turing test. Captcha refers to ‘Completely Automated Public Turing test to tell Computers and Humans Apart’. Please note that Captcha is the converse of the Turing test, devised by legendary mathematical and computing genius Alan M. Turing.
Turing’s theory was developed in 30s, long before human interacted with the computers. The theory said that if a human was to interact with a machine, and if he was convinced that the machine’s response was that of a human’s, then the computing system would have passed the Turing test.
Turing’s most well-known and celebrated achievement, perhaps the one easiest understood, was the work he did with Britain’s code breaking centre when he cracked German code ‘Enigma’ during World War II. His contribution there was significant for the electromechanical crypt-analysis machine he devised, Bombe, which helped the Allies listen to German secrets.
Algorithm s and Computing Machines
Turing’s most widely impacting contribution is perhaps the introduction of two key concepts — of algorithms and computing machines — that he outlined in his paper on ‘Computable Number’ in 1936, while at King’s College, Cambridge
Turing’s most lasting contribution, however, was the Turing machine. A machine or computational method, he proposed that a long piece of tape could be used to write simple instructions, allowing the machine to read an instruction at a time. The machine could then use one of its coded algorithms to process these instructions.