What is 'public key encryption'?

Public key encryption is a cryptographic method that fundamentally relies on the use of two distinct yet mathematically related keys: a public key and a private key. The public key is widely distributed and can be shared with anyone, allowing them to encrypt messages intended for the key's owner. Only the corresponding private key, which is kept secret by the owner, can decrypt these messages.

This system enhances security because even if someone intercepts the encrypted message, they would not be able to decrypt it without access to the private key. This approach effectively resolves the problem of key management commonly seen in symmetric encryption, where the same key is used for both encryption and decryption, thus requiring secure exchange of the key between parties.

In contrast to other responses, public key encryption does not employ a single encryption key, nor is it limited to private networks or simply a technique for concealing data. These distinctions underscore the pivotal role that the dual-key system plays in ensuring secure communications in various applications, such as secure emails, digital signatures, and data integrity verification.