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Journey into Cryptography
Explore how we have hidden secret messages through history.
What is Cryptography? A story which takes us from Caesar to Claude Shannon.
Brit explains the Caesar cipher, the first popular substitution cipher, and shows how it was broken with "frequency analysis"
Type a message in the top box, then click and turn the wheel to encrypt it.
Did you know that when you communicate you are following
a pattern without realizing it?
1. Why do we follow this pattern without thinking?
2. Would it be different for different languages?
3. How could we ...
Brit introduces the polyalphabetic cipher, which creates a lighter fingerprint than the Caesar cipher.
Try out a polyalphabetic cipher
Explore how random shifts flatten your frequency fingerprint
Can you tell the difference between actions based upon flipping a coin and those based upon blind guessing or simulating randomness? This short video examines the frequency stability property.
Can you fake a coin flip?
Determine if a sequence of heads and tails was generated with a fair coin, unfair coin, or human guesses.
WW2 Encryption is explored with a focus on the Enigma. Read more here.
Claude Shannon's idea of perfect secrecy: no amount of computational power can help improve your ability to break the one-time pad
Random vs. Pseudorandom Number Generators
generate pseudorandom vs. random walks