cryptography

Text and illustrations introduce various codes and ciphers and give examples of their use throughout history.

This book discusses different methods of secret communications used by spies, such as Morse code, the Enigma machine, the Navajo language, and digital steganography, as well as career information on espionage.

Amy and Dan travel to a distant land to follow in the footsteps of their most formidable ancestor yet, a military leader who teaches them the art of ancient warfare.

Discusses different methods for creating secret codes.

Discusses different code-breaking methods and how they have been used throughout history.

Siblings Amy and Dan Cahill continue their global search for the clues that will unlock the Cahill family's secret power while also working to evade Irina Spasky.

Readers are challenged to decipher secret messages, coded diary entries, cryptic inscriptions, and mysterious symbols in an attempt to locate a hoarde of lost treasure from the ancient civilization of the Bilongi Islands.

Amy and Dan, following a clue found in Book 3, set out to uncover details about the origins of the rivalry between the Tomas and Ekaterina branches of their family, not realizing they are headed right into the hands of the enemy.

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.

Amy and Dan Cahill are in the lead to find thirty-nine clues that safeguard a great power, and are in possession of a coded sheet of Mozart's music that will help them find the next clue while their relatives follow in close pursuit. Includes cards.