Murderous Maths: Secret Life of Codes
Kjartan Poskitt, Philip Reeve
The fun in codes lies in the making and the breaking, and in The Secret Life of Codes readers will learn the art of encoding and decoding, and even how to make their own Enigma machine. Using a host of hilarious characters, Kjartan Poskitt presents all the tricks, tips and shortcuts to maths they don’t teach at school.
Reviews

Reading this book was great and it explained a lot of interesting things i didn’t already know!
Madam Sunny Lavalamp 03.09.2023

I loved the part where they explained a bout the engima machine.
Doctor Harmonica Armadillo 08.08.2020