Computer Science Illuminated, 7th Edition

17.4 Cryptography

A technical approach to keeping information secure can be discussed under the general umbrella of cryptography, which is the field of study related to encoded information. The word cryptography comes from the Greek term for “secret writing.” The basic concepts of cryptography have been used in one form or another for thousands of years to help people keep secrets from falling into the wrong hands. In this section, we explore the general issues related to cryptography, as well as some of the current cryptography approaches.

Encryption is the process of converting ordinary text, referred to as plaintext in cryptography terminology, into a form that is unreadable, called ciphertext. Decryption reverses this process, translating ...