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STORYTech Stories · #13EP.229 · 24 s

Tech Story #13 · Golden Age G6: al-Kindi — the first codebreaker

Cover of the lesson: Tech Story #13 · Golden Age G6: al-Kindi — the first codebreakerComing to YouTube soon
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// WHAT YOU WILL LEARN

Baghdad, 9th century: al-Kindi wrote the earliest known description of frequency analysis (counting letters to crack secret codes) — why today's messages need strong encryption.

// LESSON NOTES

Who cracked secret codes first? 🔐📜

🏛️ Meet al-Kindi, Baghdad, about 850.
📖 He wrote the oldest known guide to breaking codes: "On Deciphering Cryptographic Messages".
🔢 His trick: COUNT THE LETTERS. In any language some letters show up far more than others.
🤔 Which letter wins in English?
✅ E! Find the most common letter in the secret message, swap it back to E, then do the rest — and the code cracks.
🔒 That's why today's apps use far stronger codes that no letter count can break.

Read the voiceover (transcript)
  1. Who cracked secret codes first?
  2. Al-Kindi, in Baghdad, about eight fifty!
  3. He wrote the oldest known guide to breaking codes.
  4. His trick: count the letters! Some show up far more.
  5. Which letter wins in English?
  6. E! Swap it back, and the code cracks!
  7. Today, apps use far stronger codes.
  8. Next: the man who measured the Earth. Follow for more!

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