Codes require a codebook. Ciphers do not.

Freemason’s Cipher or Masonic Cipher

The Freemason’s Cipher has been around a long time. It was used in the American Civil War to send secret messages.  It is also sometimes called the Pigpen Cipher. Read more history here: And try an interactive online here:

Morse Code

Until the early 1920s, radio transmissions were in Morse Code. Three things about Morse Code:

  1. Dots and dashes make it a binary code like the 0’s and 1’s used in electronics.
  2. Each letter has a signal based on its frequency in English. The code tree begins with E with one dot, and T with one dash. Then I is represented by two dots, A by a dot and dash, N with a dash and dot, M with two dashes, and so on.
  3. Morse Code Codebooks were used to lower the cost of sending telegrams, or to keep the contents a secret. Instead of sending a whole phrase or sentence, a single word could be used.

If you want to hear a message in Morse Code, the Morse Code translator at is a great place to visit. You can type in a message, translate it to Morse Code, and play it.

Caesar Cipher


Vigenere Cipher