Dan Brown's latest novel, The Da Vinci Code, published by Doubleday Books, is about the famous Renaissance artist and the oblique references to the occult contained in his equally famous paintings. It's also about ancient secret societies, modern forensics, science and engineering, and the history of religion.
Most of all The Da Vinci Code is about the history of encryption -- the many methods developed over time to keep private information from prying eyes.
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