# Is there an algorithm to hide text in another text, while preserving the meaning of the latter?

Is there a way to hide a text message $A$ inside another text $B$ using a cryptographic cipher/algorithm, while preserving the sense/meaning of $B$ and without anybody being able to notice there is a message $A$ hidden in text $B$?

I am looking for something that can be processed either manually or by a computer.

For clarification: I don't mean to hide a message like “Attack X” saying “I went to X on holiday this summer” but an actual cipher/algorithm.

I know for sure there must be something, but being new to cryptographic and not knowing much about it, I don’t know where to look or what to look for. Is there a way to achieve this? If there is, could you (besides a reference) also provide a short example?

• What you are looking for is called steganography. Questions about steganography can be on topic here, if it is the right kind of question. Commented Nov 4, 2015 at 19:24
• No, I know stenography... I don't want to add hidden messages in (image/audio/any) files but in text that can be printed or written on paper. I'm not looking to use that Commented Nov 4, 2015 at 19:39
• Steganography can be in text, text that can be printed or written on paper. For example, hide your message in the first letter of every paragraph. Here is another example Commented Nov 4, 2015 at 19:49
• I never said anything about PGP/GPG. Where did that come from? The link I sent you to mentions PGP/GPG as not a solution to the problem they are trying to solve. Commented Nov 4, 2015 at 20:41
• How about this one. Try "Linguistic Steganography" in google scholar for more, that aren't too obvious. Commented Nov 4, 2015 at 20:44

I think you can embed message $$A$$ into message $$B$$ with simple $$LSB$$, but you will have message $$B'$$ and maybe alter the meaning. If you want the message $$B'$$ to retain the original meaning, you should design $$B$$ to do that.
• Just to be sure, do you mean Least Significant Bit by LSB? Also, it seems the last $B$ is supposed to be $B'$ Commented Jan 10, 2016 at 16:42