Graphical Ciphers


There are lots of ciphers that are well known for their ability to disguise a secret message. However, can you make up one of your own ciphers? Graphical ciphers can be a lot of fun to make and can be personalized to look like a normal picture.

To start, you need to identify a set of pictures/symbols or patterns of a given picture/symbol to represent each letter of the alphabet. The example below uses a pattern to identify different letters of the alphabet. The location and number of the seahorses determine the letter represented in the cipher key below.



Now that you have a different pattern for each letter of the alphabet you can use the cipher key above to write a letter with a secret cipher attached. Perhaps you'll write up a fake letter about your recent trip to the ocean and talk about the amazing seahorses. Of course you'll draw a picture to go along with your letter, your secret graphical cipher! You can easily substitute the seahorses with just about any other small picture such as a bee, flower, etc. Encipher a message using the key above and then answer the questions: 1) Why are graphical ciphers not used very often? Do graphical ciphers work well for short messages? Long messages? Why would you use a graphical cipher rather than an alphabet substitution cipher?