The Bacon cipher is a cipher and steganography method dating back to Francis Bacon.
First, a five-digit code consisting of the letters A and B is assigned to each letter of the original text.
Subsequently, this coding is hidden in a text. There are several methods for this:
Two different fonts can be used for the individual letters of a text. One font stands for the letter a, the other for the letter b: “This is an almost inconspicuous message, isn’t it?” Francis Bacon developed a handwriting of 21 characters for this purpose, in which there are two different forms for each upper and lower case letter. This is the original form of the Bacon cipher.
Instead of using different fonts, lowercase letters can be used for “a” and uppercase letters can be used for “b”: “Tis a FasT uNfÄLLige NachriCHt, Or is it?”
Form a sentence in which the first letters of the words stand for the letters “a” and “b.” If a word begins with one of the letters A-M, it stands for “a.” Words beginning with N-Z stand for “b”. Example: “Winter at the North Pole is usually the same. Only at the beginning it is strange. But then you get used to it. Water and ice are very cold. The polar bear swims in the sea. Help is usually not available. But never give up. I’m only a kilometer away after all.”
If one does not want to disguise the transmission of a secret message, the Bacon cipher can also be used for encryption. Here one chooses for each “a” randomly one of the letters A-M, for each “b” one of the letters N-Z: “SDUAG MTBAH JQCLN EZEBI AVOXK MATHE BACON BXDFH DKCEI”.