Invented by Blaise de Vigenère, the cipher is a more complex form of the Caesar cipher; in this case by using multiple alphabets. To encrypt a message, you need a keyword and a set of alphabets (a matrix). To encrypt you take the first letter of the keyword and find it in the column, and the first letter of plaintext and match it with the associated row. For example, the first letter of the keyword is P and plaintext is C; the encrypted text is R.
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