Tech WondersPlay

Codes, Cryptography & BlockchainNumber Theory

The Prime Lock

Multiplying is easy; un-multiplying is the secret behind online security

Multiplying two numbers takes seconds. So why can undoing it guard the padlock in your browser?

You'll find out

  • Numbers that refuse to split
  • Why bigger primes mean a longer hunt
  • A 1977 challenge and its magic words

Why it matters

Locks built on this one-way trick help protect logins, payments and software updates every day.

About 3 min6 interactive slides · 5 questionsLesson 170 · Zone 19

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