It also differs from cryptology, which refers specifically to the study of codes.
The world is derived from Greek words meaning ‘secret’ and ‘writing.
WhatsApp, the popular chat app, has introduced end-to-end encryption for the messages of all of its users.
Cryptography is not a new concept in the computer age, however. For example, Julius Caesar gave his name to one of the earliest known ciphers, the Caesar cipher. This shifts every letter in the alphabet a certain number of places in the alphabet. For example, B stands in for A, C stands in for B, etcetera.
Cryptography is often a core module in cyber security courses. It requires a knowledge of programming as well as some understanding of probability and theory of computation and algorithm analysis.
Key topics include encryption, pseudo-random generation, digital signatures, two-party protocols and zero-knowledge.