The human genome is represented by a sequence of 3 billion As, Cs, Gs, and Ts. With such large numbers, sequencing the entire genome of a complex organism isn't just a challenge in biochemistry. It's a logistical nightmare, which can only be solved with clever algorithms.

The prime numbers are the atoms amongst the integers, and while we know that there are infinitely many of them, there's no general formula that generates them all. Julian Havil looks at a little-known algorithm that sieves out all primes up to a given number, and which is astonishing in its simplicity.

What does a mathematician from the 3rd century BC have to do with tuning musical instruments in 17th century Europe? Benjamin Wardhaugh tells us about one of the more unusual places you might find Euclid's algorithm being used.

Numbers are bandied around all the time in sports coverage - and cricket is particularly rich in statistics and rankings. It has probably not escaped your attention that the World Cup of cricket has just finished in South Africa (Australia won - again) and so to mark the occasion, Rob Eastaway tells Plus what it takes to be the best.

A test invented by the mathematician Alan Turing in 1950 is helping to stop spammers.

Clearly the modern electronic computer couldn't have been built before electronics existed, but it's not clear why computers powered by steam or clockwork weren't invented earlier. Tom Körner speculates on the historical reasons why computers were invented when they were.

We take reliable radio communications for granted, but accommodating many different users is not easy. Robert Leese explains how the mathematics of colouring graphs can help avoid interference on your mobile phone.

Practical problems often have no exact mathematical solution, and we have to resort to using unusual techniques to solve them. From navigation in the 17th century to postage stamps, see how this principle applies to a variety of real-life problems - and also learn how to use a piece of string to locate a German bomber!