Public-key cryptography, also known as asymmetric cryptography, is a form of
cryptography in which a user has a pair of
cryptographic keys - a public key and a private key. The private key is kept secret, while the public key may be widely distributed. The keys are related mathematically, but the private key cannot be practically derived from the public key. A message
encrypted with the public key can be decrypted only with the corresponding private key.
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