Societal Impact
Privacy & Security
How a message stays secret even when everyone can watch it travel.
1
A lock anyone can close
Modern encryption hands everyone an open padlock (a public key). Anyone can lock a message to you, but only your private key opens it.
2
Easy one way, impossibly hard the other
Multiplying two big primes is instant; un-multiplying the result is effectively impossible. That gap is what keeps your data private.
3
Why it matters to you
Every login, payment, and private message rides on this math. Knowing it exists, and its limits, is part of being safe online.
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