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Mathematics

Public Key Cryptography and the Mathematics Behind RSA Encryption

Quick fact

RSA encryption uses a pair of keys—a public key for encrypting and a private key for decrypting—yet the security of the entire system rests on the fact that while multiplying two large prime numbers is easy, figuring out which two primes created a given product is computationally infeasible.

Why this is interesting

You've probably seen a padlock icon in your browser, but did you know that the security behind that tiny symbol relies on a centuries-old mathematical puzzle? How can we share a secret key without anyone else intercepting it?