HVAC stands for Heating, Ventilation, and Air Conditioning. It is a system of technologies used to regulate the temperature, humidity, and air quality of a building or space. HVAC systems are designed to provide a comfortable environment for occupants while also conserving energy. They typically include components such as air handlers, furnaces, boilers, heat pumps, and air conditioners. HVAC systems are used in both residential and commercial buildings to ensure a comfortable and healthy indoor environment.