What is the process of transforming data into a format unreadable by unauthorized users called?

The process of transforming data into a format that is unreadable by unauthorized users is known as encryption. This technique is used to protect sensitive information by converting plaintext into ciphertext through the use of algorithms and cryptographic keys. Only those with the appropriate decryption key can revert the ciphertext back to its original, readable form, ensuring that unauthorized users cannot access the data even if they are able to intercept it.

Encryption serves as a vital security measure in various contexts, such as securing communications over the internet, protecting data stored on devices, and safeguarding sensitive information in transit. It ensures confidentiality, integrity, and authenticity of data, which are crucial aspects of cybersecurity.

In contrast, other processes listed do not serve the same purpose as encryption. For instance, hashing generates a fixed-size output (hash) from input data, which is typically used for data integrity checks rather than confidentiality. Encoding modifies data into a different format for transmission or storage, making it reversible but not focusing on security. Decoding is simply the reverse process of encoding, translating data back into its original format without providing any protection against unauthorized access.