Codes, Cryptography & BlockchainCodebreaking
Counting Letters Breaks Codes
A 9th-century scholar cracked substitution ciphers with a tally chart
A message written in strange symbols looks unbreakable. Over 1,100 years ago, a scholar in Baghdad explained how to read them without the key.
You'll find out
- How many keys a symbol swap has
- Which symbol to crack first
- When counting letters fails
Why it matters
It's codebreaking's oldest trick, and any cipher worth using, up to the ones guarding your phone, must beat it.
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