What type of burglar alarm is designed to emit sound when triggered?

The type of burglar alarm that is designed to emit sound when triggered is an audible burglar alarm. This system is specifically intended to alert individuals nearby, as well as possibly deter intruders, by producing a loud sound—such as a siren or horn—when unauthorized access is detected. The primary function of an audible alarm is to make a noticeable noise that draws attention to the situation, prompting a response from the property owner or law enforcement.

In contrast, a silent burglar alarm is designed to prevent triggering any noise, typically sending a signal discreetly to a monitoring service or police without alerting the intruder. A video surveillance system is focused on recording and monitoring activities rather than providing an immediate audio alert. Lastly, a motion sensor alarm can be part of either an audible or silent system, detecting movement but not necessarily defined by producing sound. Thus, the distinction lies in the audible alarm's key function of generating an immediate, loud alert to notify the surrounding area of a possible break-in.