The answer is encryption
steganography would be hiding data, like in an image
digital forensics is the analysis done after an attack
and the last one is a security standard
An unfavorable opinion or feeling formed beforehand or without knowledge, thought, or reason.
2.
any preconceived opinion or feeling, either favorable or unfavorable.
3.
unreasonable feelings, opinions, or attitudes, especially of a hostile nature, regarding an ethnic, racial, social, or religious group.
4.
such attitudes considered collectively:
The war against prejudice is never-ending.
5.
damage or injury; detriment:
a law that operated to the prejudice of the majority.