One of the most popular security devices used at homes is the motion detector alarm. Motion detectors are always set in place to trigger an alarm.  If the radar detects any movement or a beam of light is disrupted, the alarm will go off.  This is the basic job of a motion detector.  There are other uses of motion detectors aside from being an alarming device.

Automatic doors in groceries use motion detectors as well.  Whenever a person steps in the way of the detector, the door opens. This works with lights as well. Especially those garage doors or porch lights that will automatically turn on when motion is detected. You won’t have to turn on any switch and the lights will turn off automatically as well after a few minutes.