What are symmetric encryption algorithms?

Symmetric encryption algorithms rely on a single shared key for both the encryption and decryption processes. This means that the same key is used to transform plaintext into ciphertext and then back into plaintext. The strength of symmetric encryption comes from the secrecy of the key; if both the sender and the recipient have access to this key and keep it confidential, data can be securely transmitted.

In contrast, methods that use two different keys refer to asymmetric encryption, which involves a public key for encryption and a private key for decryption. Additionally, the options describing algorithms that only encrypt data or do not require a key for operation are not accurate representations of how symmetric encryption functions. Effective symmetric encryption necessitates a shared secret to maintain security throughout the encryption process.