|A security alarm is a system designed to detect intrusion unauthorized|
entry into a building or area. Security alarms are used in residential,
commercial, industrial, and military properties for protection against
burglary (theft) or property damage, as well as personal protection against
intruders. Car alarms likewise protect vehicles and their contents. Prisons
also use security systems for control of inmates.
Some alarm systems serve a single purpose of burglary protection;
combination systems provide both fire and intrusion protection. Intrusion
alarm systems may also be combined with closed-circuit television
surveillance systems to automatically record the activities of intruders,
and may interface to access control systems for electrically locked doors.
Systems range from small, self-contained noisemakers, to complicated,
multi-area systems with computer monitoring and control.