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SIMPLEExplained Simply · #11EP.184 · 24 s

How does a QR code hold a link?

Cover of the lesson: How does a QR code hold a link?▶ Tap to play
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// WHAT YOU WILL LEARN

Black and white squares are bits; built-in error correction lets the code still work with up to about 30 % of it damaged.

// LESSON NOTES

How does a little square hold a whole link? 📱🔳

⬛ Each tiny square is a bit: dark = 1, light = 0.
🔤 Your link becomes letters, letters become bits (8 per letter: 'e' = 01100101), bits become squares.
🎯 The 3 big corner squares show your camera where the code is and which way is up.
🩹 Rip off up to about 30 % and it still works — spare bits (error correction) rebuild the rest.
🏭 Invented in 1994 in Japan (Denso Wave) to track car parts.

Read the voiceover (transcript)
  1. How does a little square hold a whole link?
  2. Each tiny square is a bit: dark is one, light is zero!
  3. Your link becomes letters, then bits, then squares.
  4. Three big corner squares show the camera which way is up!
  5. Guess: how much can you rip off?
  6. Up to thirty percent, and it still works!
  7. Spare bits rebuild the rest!
  8. Next: why electric cars launch so fast. Follow for more!

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