Presents an overview of various types of codes and ciphers used throughout history, famous cryptologists, and how to create your own secret messages.

Presents a guide to codemaking, codebreaking, and their role in history, describing different types of codes and ciphers, discussing codebreaking and concealment techniques, and including brief stories about exciting moments in the history of the art.

A fascinating exploration of the uncrackable codes and secret cyphers that helped win wars, spark revolutions and change the faces of nations.

"Discusses different methods for breaking secret codes"--Provided by publisher.

Sly uses her detective skills to help her friends solve mysteries that all involve some kind of code.

The Cahills are the world's most powerful family, but their strength is being tested. A sinister man calling himself The Outcast has targeted the family and set them an impossible test. He's recreating four of history's worst disasters and challenging the young Cahills to find and stop the tragedies before it's too late. Now, with one disaster behind them, siblings Dan and Amy Cahill and their friends have just days to discover what the Outcast's...

The clock has run out for thirteen-year-old Dan Cahill. As head of the most powerful family the world has ever known, he and his older sister, Amy, have been in the crosshairs for too long. Dan and Amy have always managed to stay a step ahead of their enemies, but it was only a matter of time until luck failed them. Now Dan is hopelessly trapped and nothing can save him except unleashing an evil into the world even worse than the enemies closing in....

Explore the history of codes from The Haircut Code, used by the Persians to convey messages in war, to Ancient Hebrew ciphers, pictorial codes of the Egyptians Mayans to letter codes in ancient Rome and substitution ciphers used in Tudor England when the execution of Mary, Queen of Scots was being planned. Find out about modern-day codes, such as tennis players Laura Robson and Heather Watson's 'back slang' when playing doubles and computer codes...

Using their code-breaking skills, four middle-schoolers solve the mystery of the eccentric man who draws stick figures on his second-floor bedroom window.