# The History of Encryption ### The Caesar Cipher A substitution cipher. Either you can shift to the right or to left by any number of spaces you like. ### ROT 13 Single alphabet substitution cipher. ### Multi-Alphabet Substitution In this scheme, you select multiple numbers by which to shift letters (that is, multiple substitution alphabets). ### Rail Fence A type of transposition cipher. ``` A tc a dw ta k ta n ``` Becomes: **atcadwtaktan** ### **Vigenère** Vigenère is a polyalphabetic cipher and uses multiple substitutions in order to disrupt letter and word frequency. ### **Enigma** The Enigma is a sort of mechanical polyalphabetic cipher. The operator of the Enigma machine would be given a message in plaintext and then type that message into Enigma. For each letter that was typed in, Enigma would provide a different ciphertext based on a different substitution alphabet. The recipient would type in the ciphertext, getting out the plaintext, provided both Enigma machines had the same rotor settings. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://wiki.zacheller.dev/network-security/courses/isci-cnss-course/fundamentals-of-encryption/the-history-of-encryption.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.