A security system refers to a set of measures and devices designed to protect people, property or information from harm, loss or unauthorized access. These systems can include physical barriers such as locks, alarms, surveillance cameras, motion detectors, and other electronic security measures like biometric scanning, access control cards, and secure networks. The goal of a security system is to provide safety, prevent crime or vandalism, and deter potential threats while also ensuring the privacy and well-being of those being protected.