What is the process of converting plaintext messages to ciphertext messages called?

The process of converting plaintext messages into ciphertext messages is called encryption. Encryption is a fundamental concept in cybersecurity, as it protects sensitive information by transforming it into a format that is unreadable without a specific decryption key or method. The primary goal of encryption is confidentiality, ensuring that even if the data is intercepted, it cannot be understood without the appropriate credentials.

While coding, encoding, and obfuscation are related concepts that may involve altering data or information, they do not specifically refer to the transformation from plaintext to ciphertext. Coding typically refers to the representation of information in a certain format, which does not inherently provide security. Encoding is the process of converting data into a different format using a scheme that is publicly available; it is often used for data integrity and transmission but does not provide security against unauthorized access. Obfuscation refers to making data obscure or confusing, often used in software development to protect source code, but it does not involve encryption's mathematical algorithms or keys.

Therefore, encryption is the most accurate term for the process of transforming plaintext into ciphertext, focusing on the secure protection of information.