Plus.Maths.org
theoretical computing
Debate surrounds $25000 prize won by undergraduate for solving universal Turing machine problem
A test invented by the mathematician Alan Turing in 1950 is helping to stop spammers.
Mike Yates looks at the life and work of wartime code-breaker Alan Turing. Find out what types of numbers we can't count and why there are limits on what can be achieved with Turing machines.