A home alarm system, on the other hand, is effective against both burglaries and robberies
. The alarm company will place sensors on all of your doors that will detect when they've been opened. As soon as an unauthorized entry is detected, the alarm will sound loudly and local police will be dispatched to your residence. A criminal with even an ounce of sense will take off as soon as they hear the alarm as they would most likely end up in jail if they don't.