HVAC systems, which stands for Heating, Ventilation, and Air Conditioning, are essential for maintaining comfortable indoor environments. They work by regulating temperature, humidity, and air quality in homes and buildings. The heating component warms the space during cold weather, while the air conditioning cools it down in the summer. Ventilation is crucial as it ensures fresh air circulates throughout the area, removing stale air and pollutants. Together, these systems help create a pleasant atmosphere, making them vital for both residential and commercial spaces. Proper maintenance of HVAC systems can lead to energy savings and improved air quality.