Symmetric vs Asymmetric Encryption
Encryption is a core part of cryptography, and understanding the difference between symmetric and asymmetric methods is crucial.
Symmetric encryption uses the same key to encrypt and decrypt data. This makes it fast and efficient, but securely sharing the key between parties can be difficult. Examples include AES and DES.
Asymmetric encryption uses a pair of keys: a public key to encrypt and a private key to decrypt. This solves the key-sharing problem, but it is slower than symmetric encryption. Examples include RSA and ECC.
In practice, most secure systems combine both: asymmetric encryption securely shares a symmetric key, which then encrypts the bulk of the data. This is how many messaging apps and HTTPS connections work.