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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? Questions: 1. Why do we follow this pattern without thinking? 2. Would it be different for different languages? 3. How could we avoid this?
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.
Input a long list of 0's and 1's into the text field with your EYE'S CLOSED - how uniform are you?
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