Symmetric cryptography is a type of cryptography that uses the same key for both encryption and decryption of data. An example of symmetric cryptography is the Advanced Encryption Standard (AES).
Asymmetric cryptography, also known as public-key cryptography, uses two different keys for encryption and decryption of data. One key is used for encryption and the other for decryption. An example of asymmetric cryptography is the RSA algorithm.