Shift Ciphers

The other week I guest taught a lesson on encryption. I only had about 30 minutes, so I couldn’t cover all of what I had written. Here is most of what I wrote. I hope my \LaTeX code compiles correctly.

 

Caesar Cipher or Fdhvdu flskhu

Encryption allows us to send messages to each other without others knowing what that message is. Here we will explore one of the most basic, yet unsecure types of ciphers, the Caesar Cipher.

To encrypt a message using the Caesar cipher we begin by placing two alphabets on top of one another. The top (lower-case) line will be our plain text, the bottom will be our cipher text.

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