Symmetric vs Asymmetric Encryption
Symmetric encryption uses the same key to encrypt and decrypt, it is fast and efficient (AES is the standard), but both parties need the same secret key, which creates a key-distribution problem. Asymmetric encryption uses a mathematically linked key pair, a public key anyone can use to encrypt, and a private key only the owner holds to decrypt, solving the distribution problem at the cost of being much slower.
Symmetric Encryption
Asymmetric Encryption
Use Symmetric Encryption when
You need to encrypt large amounts of data quickly and both sides can already share a key securely.
Use Asymmetric Encryption when
You need to establish trust or exchange a key with someone you have never securely communicated with before.
They are complementary, not competing. TLS uses asymmetric encryption during the handshake to safely agree on a symmetric key, then switches to that fast symmetric key for the actual session.
Study this on the roadmap