What are the essential ingredients of a symmetric cipher?

•  A symmetric encryption scheme has five ingredients:
•  Plaintext: This is the original intelligible message or data that is fed into the algorithm as input.
•  Encryption algorithm: The encryption algorithm performs various substitutions and transformations on the plaintext.
•  Secret Key: The secret key is also input to the encryption algorithm. The key is the value independent of the plaintext. The algorithm will produce a different output depending on the specific key being used at the time. The exact substitutions and transformations performed by the algorithm depend on the key.
• Cipher text: This is the scrambled message produced as output. It depends on the plaintext and the key.
• Decryption algorithm: This is essentially the encryption algorithm in reverse. It takes the cipher text and the secret key and produces the original plaintext.