Exploring RSA Encryption in OpenSSL
Symmetric vs. Asymmetric Encryption
The best way to understand asymmetric encryption is to think of a box that has two kinds of keys: one key locks it and the other unlocks it. Anybody who has a copy of the locking key (aka public key) can put a secret in the box. Because only you have the unlocking key (aka private key), nobody else can reveal a secret that someone else locked in the box. This is different from symmetric key encryption, in which the same key is used for locking and unlocking.
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