Alarm device

[3] Often explained as the off-stage sounds of conflict or disturbance,[4] recent research suggests a bell or drum may have been used to rouse soldiers from sleep.

[3] Early alarm devices were often bells, drums, other musical instruments, or any items which made unusual loud noises that attracted the attention of the surrounding population.

With the advent of electricity, a variety of other alerting devices have been invented, such as buzzers, klaxons, sirens, horns, flashing and coloured lights, and other all-purpose alarms.

[citation needed] Human reactions to an alarm will often depend on upbringing, psychological training, or the behavior of others in the environment.

Some alarms may startle and cause a fight-or-flight response in humans; a person under this mindset will panic and either flee the perceived danger or attempt to eliminate it, often ignoring rational thought in either case.

They can be triggered for several reasons, such as the movement of pets,[6] typing in the wrong security codes, or loud sounds from windows or doors.