This document provides information about computer security, including definitions, types of security threats, and security measures. It discusses hardware, software, data, and network security. Security threats include viruses, Trojan horses, worms, hackers, and natural disasters. Security measures to address these threats include data backups, cryptography, antivirus software, anti-spyware software, firewalls, and ensuring proper human security procedures are followed. The relationship between security threats and measures is that threats can come in various forms, while security measures are implemented to prevent unauthorized access or damage from these threats.