On the sad news of Stephen Hawking's passing we look at his professional life and work. The image shows Hawking enjoying zero gravity in 2007 and is courtesy NASA.

Some problems are so complex that, although we know how to solve them in theory, it would take billions of years to find a solution even on the fastest supercomputer. Come on a trip through the world of complexity and meet the famous P versus NP problem.

Is the proposed ABBA rule for penalty shootouts really fairer than the existing rule? Maths shows that it is, and also suggests another, more subtle rule.

We talk to pioneering mathematician and computer Scientist Stephen Cook, who came up with the concept of NP-complete problems, about his work, computers, and artificial intelligence.

Compound interest is the curse of debt and the blessing of saving. Find out how it works and what it has to do with one of the most important numbers in mathematics.