The technology used to secure communications over a computer network is encryption. Encryption converts data into a code to prevent unauthorized access, ensuring the confidentiality and integrity of the information transmitted. Protocols like SSL/TLS are commonly used to encrypt data during transmission over the internet, safeguarding against eavesdropping and man-in-the-middle attacks. Additionally, VPNs (Virtual Private Networks) utilize encryption to secure connections across public networks. By encrypting data in transit and at rest, organizations can protect sensitive information from breaches and maintain user trust.