Caesar Cipher
In cryptography, a Caesar cipher, also known as Caesar's cipher, the shift cipher, Caesar's code or Caesar shift, is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a shift of 3, A would be replaced by D, B would become E, and so on. The method is named after Julius Caesar, who used it in his private correspondence.
How it works?
Plain: ABCDEFGHIJKLMNOPQRSTUVWXYZ
Cipher: DEFGHIJKLMNOPQRSTUVWXYZABC
The encryption can also be represented using modular arithmetic by first transforming the letters into numbers, according to the scheme, A = 0, B = 1,..., Z = 25. Encryption of a letter 
by a shift n can be described mathematically as,
by a shift n can be described mathematically as,
Decryption is performed similarly,
- following shows a message :
Ciphertext: WKH TXLFN EURZQ IRA MXPSV RYHU WKH ODCB GRJ Plaintext: the quick brown fox jumps over the lazy dog
History!
The Caesar cipher is named after Julius Caesar, who, according to Suetonius, used it with a shift of three to protect messages of military significance. While Caesar's was the first recorded use of this scheme, other substitution ciphers are known to have been used earlier.
ABOUT THE AUTHOR
Hello, I am Piyush Ranjan, a computer engineering student from India. I love coding and talking on technology. Most of the time I am glued to my laptop watching movies, listening songs, blogging or coding.
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