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History of Cryptography Developments in cryptography | Period | Development | 2000 BC | In Egypt, hieroglyphics were used in inscriptions. | 500-600 BC | Hebrews used the atbash method for encryption. In this method, each letter of the alphabet mapped to a different letter to hide the true meaning of a word. | 487 BC | The Spartans used the scytale for encryption – messages were written on paper wrapped around a wooden rod. The paper was then unwrapped and sent. The recipient could read the message only by wrapping this paper on a rod of the same length and diameter. | 100-44 BC | Julius Caesar used an encryption method similar to the atbash method. He shifted each letter of the alphabet by a fixed number of places to send encrypted messages. | 1379 | Gabrieli di Lavinde developed the nomenclator. | 1466-1467 | The first polyalphabetic cipher was invented, which was much stronger than the nomenclator. | 1518 | Johannes Trithemius invented a steganographic cipher in which each letter was represented as a word taken from a succession of columns. | 1553 | Giovan Batista Belaso introduced the use of a passphrase as the key for a repeated polyalphabetic cipher. In 1563, Giovanni Battista Porta introduced the digraphic cipher and classified ciphers as transposition, substitution, and symbol substitution. | 1585 | Blaise de Vigenere developed the polyalphabetic substitution cipher. William Frederick Friedman published a book on cryptography, and is known as the "Father of Modern Cryptography". | 1623 | Sir Francis Bacon described the biliteral cipher – known as 5-bit binary encoding. This advanced the steganopgraphic cipher by using variation in the type face to carry out encoding. | 1917 | Gilbert S. Vernam invented a polyalphabetic cipher machine that used a never-repeating random key. | 1919 | A rotor-based cipher machine was invented, which

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