What is the difference between HVAC and ventilation?

HVAC stands for Heating, Ventilation, and Air Conditioning, and is a system that is used to control the temperature, humidity, and air quality of a space. It is composed of several components, including a furnace, air conditioner, and ductwork. Ventilation, on the other hand, is the process of exchanging air between the inside and outside of a space. It is typically used to bring fresh air into a space, remove stale air, and control the temperature and humidity. Ventilation is an important part of an HVAC system, as it helps to ensure that the air quality is maintained and that the temperature and humidity are kept at comfortable levels.