Acrostic – Text formed from parts of another text

Canary trap – Method for exposing an information leak

Covert channel – Computer security attack that creates a capability to transfer information between processes that are not supposed to be allowed to communicate

Cryptography – Practice and study of secure communication techniques

Deniable encryption – Encryption techniques where an adversary cannot prove that the plaintext data exists

Polybius square – Type of code

Security engineering – Process of incorporating security controls into an information system

Semiotics – The study of signs and sign processes

Audio watermark – Electronic identifier embedded in an audio signal

image steganography

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