"People ... have done computing for thousands of years," says Moshe Vardi, a distinguished computer science professor at Rice University who is working closely with Cerf on the upcoming ACM celebrations. "But the theory of computing really started in the 20th century, and Turing is one of the foremost -- if not the foremost -- parents of the theory of computing."

Both Vardi and Cerf -- who are influential figures in computer science in their own rights -- cited the idea of computability, or the ability to solve a problem efficiently, as a foundational concept for the development of modern computers.

"Businesses don't even realize how much they rely on [the idea]," says Vardi. "Today, when you have people doing algorithmic trading on Wall Street, they are following in Turing's footsteps. ... There is a line of development, each one following the other, that led from the question 'what is computable?' to the world you see around us today."

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