How hard would it be to make an encryption system that produces a normal-looking text, which can only be decrypted with a specific key?
Many steganography systems use images or video or sound, but are 'proof of concept' - toys for learning - rather than serious tools. This, unfortunately, includes many of the steganography systems described as serious tools.
One of the problems of hiding text in text is persuading people not to re-use the cover text.
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