Codes and Ciphers


Braingle: Codes, Ciphers, Encryption and Cryptography
Cryptography is the discipline of using codes and ciphers to encrypt a message and make it unreadable unless the recipient knows the secret to decrypt it.
Pigpen / Masonic Cipher   


Ciphers By Ritter: Cryptography and Technology
Revolutionary new cipher designs. An introduction to crypto, crypto glossary, technical papers, Usenet discussions and crypto links.


Codes and Ciphers in the Second World War
Between 1939 and 1945, the most advanced and creative forms of mathematical and technological knowledge were combined to master German communications.


Introduction to Cryptology - University of Rochester
Classic ciphers and attacks and variations on them: Caesar shift, monoalphabetic substitution, one-time pad, affine cipher, Vigenere cipher, Hill cipher, block permutations, etc.


Historical Cryptography
Trinity College Department of Computer Science.


Famous Unsolved Codes and Ciphers
This is an unofficial list of well-known unsolved codes and ciphers. A couple of the better-known unsolved ancient historical scripts are also thrown in, since they tend to come up during any discussion of unsolved codes.


Letter frequency -
The frequency of letters in text has often been studied for use in cryptography, and frequency analysis in particular. No exact letter frequency distribution underlies a given language, since all writers write slightly differently.
Pigpen cipher    Cipher    Classical cipher    Uncracked codes and ciphers   


Secret Language
When you were a kid, did you have a "Captain Midnight" decoder ring? With it, you could send messages to friends that no one else could read. Or perhaps you remember using special symbols to write notes to your "squeeze" in class.


International Phonetic Alphabet
Consonants (Pulmonic), Consonants (Non-Pulmonic), Diacritics, Other Symbols, Suprasegmentals, Tones & Word Accents, Vowels.


Morse Code and Phonetic Alphabets
A listing of the Morse code including punctuation and non-English letters, Java Morse Code Translator, Morse Code Frequently Asked Questions.


Codes and Ciphers
In the opinion of one of the greatest cryptologists of all time, William F. Friedman, the invention of writing formed the true beginning of civilization. But not too long after writing really got established, various people found a need for writing that could only be read by an intended recipient, but not anyone else.


Codes and Ciphers - Marcus Schaefer
Courses taught at DePaul University.


Secret Code Breaker
These pages contain small excerpts from the Secret Code Breaker series of publications. This series of cryptography publications for young readers provide detailed instructions explaining how to "crack" secret codes and ciphers for beginning cryptanalysts.
Caesar Cipher   


Cryptology: The Science of Secret Codes and Ciphers
The word Cryptology comes from the Greek word kryptos, which means hidden and logos, which means word. It is the branch of science that deals with secret communications. To keep communications secret, it is necessary to use a code, a cipher, or both.


Codes, Ciphers, & Codebreaking
Codes, ciphers, and codebreaking have been around for millennia, with the survival of nations sometimes hanging on the security of codes and ciphers. With modern computer networking, they have become important in day-to-day life. This document provides a technical and historical introduction to codes, ciphers, and codebreaking.


Social Intellect Reformation
The Brasseur Universal Code is a system of symbolic logic characters. Each of the symbolic logic characters has an inherent quality that allows the character to project a resonant harmonic energy field in base- two binary.




National Security Agency - NSA


Secret Codes in Slave Quilts - National Security Agency
Modern codes frequently involve number code groups and mathematical algorithms. Some older codes used alternate words, such as the Native American Code Talkers' system. It is believed that in the early and mid-1800s, slaves in America's southern states developed a code that involved quilt patterns.


CryptoKids™ America's Future Codemakers & Codebreakers - NSA
What's cryptology? Cryptology is making and breaking codes. It's so cool. We make codes so we can send secret messages to our friends. And we try to figure out what other people are writing about by breaking their codes.