Security is the protection of people, property, and information. It includes the prevention of crime, the detection and prosecution of criminals, and the application of physical security measures to prevent or deter criminal activity. The term can also refer to the safety of critical infrastructure, such as power plants and dams.
The need for security arises from the possibility that someone may attempt to harm people, damage property, or steal information. Security measures are designed to reduce the likelihood or impact of such an event. They can be divided into three general categories: physical security measures, which seek to prevent or deter criminal activity; technological security measures, which seek to detect and respond to criminal activity; and procedural security measures, which seek to prosecute criminals and recover stolen property.
Physical security measures include things like locks on doors and windows, alarm systems, surveillance cameras, fences, barriers, and guards. Technological security measures include things like intrusion detection systems, access control systems, encryption technologies, firewalls, and antivirus software. Procedural security measures include things like background checks on employees and visitors