Using a host of hilarious characters, Kjartan Poskitt presents all the tricks, tips and shortcuts to maths they don't teach at school. Readers will learn how to encode and decode their own messages in as many ways as possible. Can you see this very last paragraph is coded? (Read all the fourth words). The book demonstrates other codes you've probably never really been aware of. Stop waiting therefore and go for it.

A primer on the underlying technologies that allow computer programs to work. Covers topics like computer hardware, combinatorial logic, sequential logic, computer architecture, computer anatomy, and Input/Output. Many coders are unfamiliar with the underlying technologies that make their programs run. But why should you care when your code appears to work? Because you want it to run well and not be riddled with hard-to-find bugs. You don't want to be in the news because your code had a security problem. Lots of technical detail is available online but it's not organized or collected into a convenient place. In The Secret Life of Programs, veteran engineer Jonathan E. Steinhart explores--in depth--the foundational concepts that underlie the machine. Subjects like computer hardware, how software behaves on hardware, as well as how people have solved problems using technology over time. You'll learn: How the real world is converted into a form that computers understand, like bits, logic, numbers, text, and colors The fundamental building blocks that make up a computer including logic gates, adders, decoders, registers, and memory Why designing programs to match computer hardware, especially memory, improves performance How programs are converted into machine language that computers understand How software building blocks are combined to create programs like web browsers Clever tricks for making programs more efficient, like loop invariance, strength reduction, and recursive subdivision The fundamentals of computer security and machine intelligence Project design, documentation, scheduling, portability, maintenance, and other practical programming realities. Learn what really happens when your code runs on the machine and you'll learn to craft better, more efficient code.

Bletchley Park was where one of the war’s most famous – and crucial – achievements was made: the cracking of Germany’s “Enigma” code in which its most important military communications were couched. This country house in the Buckinghamshire countryside was home to Britain’s most brilliant mathematical brains, like Alan Turing, and the scene of immense advances in technology – indeed, the birth of modern computing. The military codes deciphered there were instrumental in turning both the Battle of the Atlantic and the war in North Africa. But, though plenty has been written about the boffins, and the codebreaking, fictional and non-fiction – from Robert Harris and Ian McEwan to Andrew Hodges’ biography of Turing – what of the thousands of men and women who lived and worked there during the war? What was life like for them – an odd, secret territory between the civilian and the military? Sinclair McKay’s book is the first history for the general reader of life at Bletchley Park, and an amazing compendium of memories from people now in their eighties – of skating on the frozen lake in the grounds (a depressed Angus Wilson, the novelist, once threw himself in) – of a youthful Roy Jenkins, useless at codebreaking, of the high jinks at nearby accommodation hostels – and of the implacable secrecy that meant girlfriend and boyfriend working in adjacent huts knew nothing about each other’s work.

A thoughtful and provocative fiction story about the science of secret codes and error correction. Sara, Derek and Jared have devised their own simple code to communicate with each other in class at school. When a written, coded message is amended en route to Sara and she gets into trouble, they start to explore how their simple code could use error correction to protect themselves against tampering by somebody.This is all a private hobby, until one day, on a school trip to a bank the class is caught up in an attempted bank robbery. Suddenly Sara, Derek and Jared's playing with codes - and with methods of error correction - has an urgent reality. The Secret Code Menace is part of the Cold Fusion series, published by Ransom Publishing, a specialist children's publisher. The series is designed for more able readers, gifted and talented children, and those who are curious, enjoy a challenge and like thinking outside the box. The Secret Code Menace is ideal for more able readers aged 9 - 12 with a reading age of 12 + .

The Secret Code Book is a short introduction to substitution ciphers. The chapters ease young readers into the concept of rotation ciphers and work their way up to the Vigenère cipher. Along the way, readers will also learn about geometric approaches to secret codes such as the Pigpen cipher. As a bonus, there is a brief description of frequency analysis and how it is used to crack secret codes. frper gpbqr obbx In addition, this book actively challenges readers with practice missions where answers are listed in the back. Also, there is a cut-out rotation template that is provided to make your very own cipher disk! After reading this book, you will have all the basic tools needed to create secret messages.

“What would it be like to keep a secret for fifty years? Never telling your parents, your children, or even your husband?” Codebreaker Girls: A Secret Life at Bletchley Park tells the true story of Daisy Lawrence. Following extensive research, the author uses snippets of information, unpublished photographs and her own recollections to describe scenes from her mother’s poor, but happy, upbringing in London, and the disruptions caused by the outbreak of the Second World War to a young woman in the prime of her life. The author asks why, and how, Daisy was chosen to work at the Government war station, as well as the clandestine operation she experienced with others, deep in the British countryside, during a time when the effects of the war were felt by everyone. In addition, the author examines her mother’s personal emotions and relationships as she searches for her young fiancée, who was missing in action overseas. The three years at Bletchley Park were Daisy’s university, but having closed the door in 1945 on her hidden role of national importance — dealing with Germany, Italy and Japan — this significant period in her life was camouflaged for decades in the filing cabinet of her mind. Now her story comes alive with descriptions, original letters, documents, newspaper cuttings and unique photographs, together with a rare and powerful account of what happened to her after the war. “Here’s a beauty of a history of some of the codebreaking girls who helped save us during the second world war. This one’s about Daisy Lawrence’s extraordinary life as a poor girl brought up in London and then chosen for top secret work at Bletchley Park. Reads like fiction.” —Books Monthly