| A | B |
|---|
| crytology | study of secret words |
| crytologist | a person who studies secret codes |
| scytale | ancient code machine using a rod and paper |
| telephone | code machine using key pad |
| encoding | putting a message into code |
| decoding | taking the message out of code |
| cipher wheel | a type of code machine using two wheels |
| steganogtaphy | process of hiding a message |
| invisible ink | make with lemon juice |
| semaphore | flags used for messages |
| American Sign Language | using hands to communicate to the deaf |
| Special Agents | a person who learns codes to send secret messages |
