What is the difference between symmetric and asymmetric cryptography?

Symmetric cryptography, also known as secret key cryptography, is a type of cryptography where the same key is used to encrypt and decrypt data. It is secure and relatively fast but requires both parties to have a copy of the key. Asymmetric cryptography, also known as public key cryptography, uses a pair of keys; a public key and a private key. The public key is used to encrypt data and the private key is used to decrypt it. It is slower than symmetric cryptography but is more secure since the private key is not shared.