The definition of a BAS (Building Automation System) is a system that is used to control and monitor the operations of a building. It is designed to provide a comprehensive view of the building’s systems, including HVAC, lighting, security, fire, and other systems. It can be used to automate tasks, such as controlling temperature, lighting, and security systems, as well as to monitor energy usage. The BAS can also be used to provide real-time data on the building’s performance, allowing for improved energy efficiency and cost savings. Additionally, the BAS can be used to detect and respond to emergencies, such as fire or security breaches. By providing a comprehensive view of the building’s systems, the BAS can help to improve safety, comfort, and energy efficiency.