Cryptographic messages have been found dating back to 1900 BC in Egypt. Julius Caesar was one of the more famous early rulers to use cryptography to communicate securely with his generals. His system, oddly called the Caesar Cipher would replace each letter with another letter a fixed distance from the first in the Latin alphabet. As the world became more literate, ciphers had to become more complex. One of the most secure handwritten ciphers uses a one time pad. Each party has a known scheme to encrypt/decrypt a message. At certain times, that scheme is thrown away and a new one implemented. This system worked well up until computers gained enough power to be able to find patterns. No matter how careful we are as humans to be random, we still have natural tendencies towards patterns that can be detected given enough information. Today, cryptography now exists in a digital realm with cryptographers and cryptoanalysts waging an electronic war.