HVAC stands for Heating, Ventilation, and Air Conditioning. It refers to the technology used to control indoor climate, ensuring comfort by regulating temperature, humidity, and air quality. HVAC systems are essential in residential and commercial buildings, providing heating in winter and cooling in summer. Plumbing involves the installation and maintenance of systems that transport water, gas, and waste in buildings. This includes pipes, fixtures, and appliances that ensure clean water supply and proper drainage. Both HVAC and plumbing are crucial for maintaining a safe and comfortable living environment.