Originating from the Arabic word for zero صفر (ṣifr), the word "cipher" spread to Europe as part of the Arabic numeral system during the Middle Ages. The Roman numeral system lacked the concept of See more

In casual contexts, "code" and "cipher" can typically be used interchangeably; however, the technical usages of the words refer to different concepts. Codes contain meaning; words and phrases are assigned to numbers … See more

There are a variety of different types of encryption. Algorithms used earlier in the history of cryptography are substantially different from … See more

In a pure mathematical attack, (i.e., lacking any other information to help break a cipher) two factors above all count:
• Computational power available, i.e., the computing power which can be brought to bear on the problem. It is important to note that average … See more

• Autokey cipher
• Cover-coding
• Encryption software
• List of ciphertexts See more

• Kish cypher See more