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Codes, Cryptography & BlockchainEncryption

The Only Perfect Cipher

A one-time pad is unbreakable if you never, ever reuse it

One cipher comes with a mathematical proof that nobody can ever break it. Spies used it, and their messages got read anyway. How?

You'll find out

  • Why every wrong guess looks right
  • What one lazy shortcut gives away
  • Why your phone doesn't use it

Why it matters

Every secret you send leans on a cipher. This is the one that can't be beaten, and the mistake that beats it.

About 3 min6 interactive slides · 5 questionsLesson 144 · Zone 16

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