This project provides a simple implementation of the Caesar Cipher, a substitution cipher where each letter in the plaintext is shifted by a specific number of positions down or up the alphabet. The ...

換字式暗号（単一換字暗号）を手動で解析するためのWebツールです。 自動解読ではなく、人間が仮説を立て、検証し、思考 ...

Learn how to implement a classic substitution cipher in C! This step-by-step tutorial walks you through encoding and decoding messages by replacing each letter with another according to a fixed key. A ...

Hill cipher cryptosystem is a linear algebra‐based classical polygraphic substitution cipher‐based technique. If the encryption key matrix (also called the key matrix) is not invertible, obtaining the ...

In 1854, Sir Charles Wheatstone invented the cipher known as "Playfair," named for his friend Lyon Playfair, first Baron Playfair of St. Andrews, who popularized and promoted the cipher. Its ...

A recent study published in the journal Cryptologia presents what its author calls the Naibbe cipher, a manual substitution cipher system that, as he demonstrates, is capable of taking texts in Latin ...