A fire alarm is a device that detects smoke or heat and sounds an alarm to warn people in a building that there is a fire. Fire alarms are an important part of fire safety, and they can help to save lives by giving people enough time to evacuate a building before it is engulfed in flames.
There are many different types of fire alarms, but they all work on the same basic principle. When the alarm detects smoke or heat, it sends a signal to a control panel. The control panel then sounds an alarm throughout the building, warning people to evacuate.