4 Safety systems the usual safety system includes bells on the door or jars tied to a rope that make a loud noise when the door opens.
These are all valid until someone finds them easy to remove.
The predecessor of the security system we know today is when a smart soul ties a pair of wires over a telephone line to the alarm panel of the local police station.
In the end, the system was updated and became the norm for families everywhere.
Today, wireless security systems are popular, easy to install and do not rely on hard
Cable telephone line.