What is the difference between symmetric and asymmetric encryption?

Choosing the right encryption type is critical for performance and security in communication systems.

Compare symmetric and asymmetric encryption methods and use cases.

Symmetric: one shared key for encrypt/decrypt (AES, DES). Fast but requires secure key distribution. Asymmetric: public-private key pair (RSA, ECC). Public key encrypts, private decrypts. Slower but solves key distribution. In practice, hybrid encryption is used: asymmetric exchanges a symmetric session key, then symmetric handles bulk data. TLS/HTTPS uses this approach.

This is one of the most commonly asked interview questions. Showing you understand both the theory and the practical hybrid approach demonstrates real-world knowledge.