fire alarms are objects that are used to alert people to fires. People often use them when there is a fire. It senses a fire with heat sensors, but often in schools there is a lever for someone to pull if they know there is a fire. I think they are important tools for people to use. People in some places disable fire alarms when they are cooking because these fire alarms are too sensitive and go off when ever it is a little hot. One time the fire alarm in my apartment went off when I was taking shower. This is important to know.