Cryptology is the study of secret communications. There are two primary
branches of study: cryptography and cryptanalysis. Cryptography is the
study of developing secret communications. Cryptanalysis is the study of
breaking secret communications.
Of secret communications, there are two primary branches: cryptographic
systems and steganographic systems. Cryptographic systems seek to secret
the
meaning of information conveyed, whereas steganographic systems seek to secret the
existence of the information itself.
Cryptogaphic systems are composed of two branches: ciphers and codes.
Cipher systems encrypt single (or groups) of letters at a time whereas code
systems encrypt whole words, phrases, or sentences at a time. The primary
difference here is that code systems operate on the level of meaning.
The result of encrypting a message [clear text] results in ciphertext.