Intrusion alarms work through 3 types of devices, called peripheral devices.
Thus, the 3 types of peripheral devices are the detectors, the control devices and the warning devices.
Detectors, as the name implies, are devices that are armed to detect possible danger or alarm situations, it can be through infrared that detect the presence of a body or through magnetic contact, which when doors and windows are open, for example, the alarm is triggered.
On the other hand, control devices are devices that allow communication between the user and the system.
It can be through keyboards, remote controls or communicators.
Finally, the warning devices are obviously the devices responsible for alerting when a dangerous situation occurs. These alerts can be given through sound or light sirens or through communication to an alarm center.