John Napier was a clever man indeed. Besides inventing the logarithm, he developed ingenious calculating devices that fully exploit the power of the positional system. In this article Chris Sangwin tells you how to make your own set of Napier's bones and perform mathemagic with an interactive checker board.

What's the risk of passive smoking? Or climate change? How big is the terrorist threat? And should we trust league tables? These issues concern all of us, but it's not always easy to make sense of the barrage of media information. David Spiegelhalter, Winton Professor for the Public Understanding of Risk, gives Plus his take on uncertainty.

Plus celebrates its 10th birthday!

Mathematicians solve the famous loop's mystery

A new Bayesian network helps predict the severity of the disease

A new mathematical model explores the time before the big bang

Graph theory helps answer Sudoku questions

Computer scientists prove how long it should take you to solve Rubik's cube

Plus celebrates its tenth birthday this year. Former editor and present executive editor of Plus, Robert Hunt, explores how maths popularisation in general, and Plus in particular, have changed over the last ten years.

Geometry is power