Encryption transforms readable data into ciphertext using an algorithm and a key, so someone who obtains the ciphertext cannot normally understand it without the required key. It protects confidentiality for data in transit, such as traffic between services, and at rest, such as files, databases, and backups. Encryption does not by itself prove who sent data, prevent tampering, or protect plaintext displayed on a compromised endpoint.
Its security therefore depends on implementation and key management. Attackers may target stolen, exposed, or overprivileged keys, weak algorithms or protocols, poor randomness, and systems that decrypt data unnecessarily. Use modern, authenticated encryption where appropriate; protect keys separately from encrypted data with tightly limited access, rotation and revocation procedures, and monitored use. Verify that encryption covers relevant backups and internal service links, while recognizing that lost keys can make recovery impossible and that encrypted traffic may still reveal metadata such as timing or endpoints.