# Symmetric Encryption

An encryption method that uses the same secret key to both encrypt and decrypt data.

**Symmetric encryption[↗](/symmetric-encryption)** is an encryption[↗](/encryption) method that uses a single, shared secret key to both scramble and unscramble data. Both the sender and receiver must have the same key, which makes it fast and efficient but requires a secure way to exchange that key in the first place.

It's widely used for encrypting large amounts of data, like files or entire disks, because it's much faster than its counterpart, asymmetric (public-key) encryption. Many real-world systems combine both: asymmetric encryption to safely exchange a key, then symmetric encryption for the actual data.