--Originally published at Computer and Information Security
Julius Caesar was a roman politician and general who used ciphers in his private correspondence, this type of encryption is one of the simplest and most widely known encryption techniques.
It is based on the substitution of letters by a fixed number of position on the alphabet, this cipher is used as the base of other, more complex ciphers such as the Vigenère cipher. In this cipher a keyword is used and the message to be encrypted is shifted the value of the corresponding letter of the keyword in the alphabet.
This cipher remained unbreakable for 3 centuries. Here is the Java code of both ciphers.
