Alan Turing's 100th birthday marked by Google doodle

The World-War II code-breaker Alan Mathison Turing's 100th birthday is being celebrated in Google doodle today. Search giant has put up a very interesting doodle, which is actually a mock-up of Turing machine and users have to spell the word 'Google' in the binary code to solve it.

Turing was an English mathematician, logician, cryptanalyst and computer scientist. He was known for his contribution to the development of computer science and providing a formalisation of the concepts of "algorithm" and "computation" with the Turing machine. He is also widely considered to be the father of computer science and artificial intelligence.

He worked for the Britain's Government Code and Cypher School during World War II and devised a number of techniques for breaking German ciphers.

Turing later created one of the first designs for a stored-program computer, the ACE.

As homosexuality was illegal in Britain in that period, Turing was criminal prosecuted for being gay in 1952. He accepted treatment with female hormones as an alternative to prison.

He died in 1954, just over two weeks before his 42nd birthday, from cyanide poisoning.

In 2009, British Prime Minister Gordon Brown apologised for the treatment meted to Dr Turing for homosexuality.