The purpose of data encryption in cybersecurity is to protect sensitive information by converting it into a secure format that can only be read by authorized users. Encryption prevents unauthorized access to data during transmission or storage, safeguarding it from potential threats such as hacking and data breaches. By using cryptographic algorithms, data is transformed into a ciphertext that requires a decryption key to revert it back to its original form. This mechanism is vital for maintaining confidentiality and ensuring the integrity of information within various sectors, including finance and healthcare.