How does asymmetric encryption differ from symmetric encryption?

Asymmetric encryption is characterized by the use of a pair of keys: a public key and a private key. This key pair is fundamental to its operation and sets it apart from symmetric encryption, which relies on a single key for both encryption and decryption. With asymmetric encryption, the public key is shared openly and can be used by anyone to encrypt messages intended for the owner of the corresponding private key. Only the owner of the private key can decrypt these messages, ensuring confidentiality. This method also enables functions like digital signatures, enhancing authentication and integrity in data transmission.

In contrast, symmetric encryption utilizes one shared key to both encrypt and decrypt data. It is typically faster than asymmetric encryption because of the simpler mathematical operations involved, but it does not support the same level of secure key distribution, as both parties need access to the shared secret key beforehand.

Thus, the defining feature of asymmetric encryption is indeed the use of a public and private key pair, which addresses varying security concerns compared to symmetric encryption.