Fire alarms are designed to alert you of the presence, risk or danger from the devastating effects of fire. There are heat detection alarms, carbon monoxide alarms and smoke alarms. The fire alarms main job is alerting you to the presence, risk or danger of fire, alert off-site facilities/authorities (Fire Department) and initiate the fire sprinklers and fire protection system.
There are manual operation fire alarms, such as pull switch that are generally located in public buildings and schools.
Automatic fire alarms, such as carbon monoxide, and smoke are generally found in most buildings including public and private residences.