What is an “intrusion detection system”?

An "intrusion detection system" specifically refers to a technology or mechanism that is designed to monitor and detect unauthorized entries or breaches into secured areas. This system is crucial for enhancing security in both residential and commercial environments, alerting property owners or security personnel to potential intrusions.

The primary function is to serve as a protective measure against theft, vandalism, and other criminal activities, providing alerts that enable timely responses to potential threats. Through a combination of sensors, alarms, and sometimes video surveillance, intrusion detection systems are tailored to differentiate between normal activities and suspicious behaviors, thus ensuring a proactive approach to security.

The other choices represent systems with entirely different functions: detecting water leaks focuses on moisture and potential flooding, monitoring air quality is concerned with environmental health factors, and managing energy efficiency pertains to optimizing energy consumption. Each of these is significant in its own right but does not relate to the primary objective of intrusion detection, which is centered on safeguarding against unauthorized access.