An introduction to secret codes, discussing the history of the art, looking at different types of codes, providing information about the Enigma machine used by the Germans during World War II and efforts to break the code by the British, describing coding languages, and including activities.
Content Note
What's so special about secret codes? -- Early codes -- Code symbols and cracking codes -- Code school and the enigma machine -- Coding languages -- Codes of today and tomorrow -- Glossary -- Find out more -- Index.