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Codes, Cryptography & BlockchainClassical Cryptography

Caesar's Cipher

Julius Caesar hid messages by shifting every letter three places

Julius Caesar hid his private letters with one simple trick. Learn it, then crack a secret message without even knowing the key.

You'll find out

  • How Caesar scrambled his letters
  • How to crack his code without the key
  • Why sharing a key is the hard part

Why it matters

Secret keys still lock your chats and payments today. Caesar's cipher shows what makes a key easy, or hard, to break.

About 3 min6 interactive slides · 5 questionsLesson 30 · Zone 4

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