A(n) or cryptosystem is an encryption method or process encompassing the algorithm, key(s) or cryptovariable(s), and procedures used to perform encryption and decryption.

A(n)  Cipher or crypto-system is an encryption method or process encompassing the algorithm, key(s) or crypto-variable(s), and procedures used to perform encryption and decryption.

Explanation:

Cryptography is such a technique that is used for the secure transfer of the information. We make codes for this purpose.Cryptosystem is such a system in cryptography is simply an encryption method that has three algorithms. One algorithm is used for the generation of key, one for encryption and decryption. Encryption is a process of converting the information in a data that is not understandable and decryption, this non-understandable data is converted into information so that we can read it.