What does a decryption key do?

A decryption key is specifically designed to reverse the process of encryption. When data is encrypted, it is transformed into ciphertext, a format that renders it unreadable to unauthorized individuals. The decryption key is necessary to convert this ciphertext back into its original, understandable form known as plaintext. This process ensures that only individuals or systems with the correct decryption key can access the original sensitive information, thus maintaining confidentiality.

In this context, the role of the decryption key is critical for secure communication and data protection. Its primary function is reaching the original content after it has been securely encoded through encryption, which safeguards the data against interception during storage or transmission.