Editing Transposition cipher (section)

{{Short description|Method of encryption}}
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[[File:Double columnar transposition example.png|thumb|400x400px|Step-by-step process for the double columnar transposition cipher.]]
In [[cryptography]], a '''transposition cipher''' (also known as a permutation cipher) is a method of encryption which scrambles the positions of characters (''transposition'') without changing the characters themselves. Transposition ciphers reorder units of [[plaintext]] (typically characters or groups of characters) according to a regular system to produce a [[ciphertext]] which is a [[permutation]] of the plaintext. They differ from [[Substitution cipher|substitution ciphers]], which do not change the position of units of plaintext but instead change the units themselves. Despite the difference between transposition and substitution operations, they are often combined, as in historical ciphers like the [[ADFGVX cipher]] or complex high-quality encryption methods like the modern [[Advanced Encryption Standard]] (AES).