What is the difference between Symmetric and Asymmetric Encryption, and which one is better?

The major difference between the two is, symmetric encryption uses 1 key, whereas asymmetric encryption uses 2 keys.

Symmetric Encryption does operations faster than Asymmetric. For this reason, Pure Asymmetric Encryption is never used. Symmetric encryption is used instead (for secure communication where asymmetric communication is preferred), and the symmetric key is exchanged using asymmetric encryption.