I don’t understand how modern heating systems work

Modern heating systems have always been an enigma to me.

I understand the older style of heating systems. The older styles of heating systems were created by allowing the wood to burn inside of a large, metal box. As long as the wood was burning, your house had heat. Those heating systems warmed through radiation, and it heated the area in from of the heating system much faster than the rest of the house. There was nothing else to these heating systems. However, at the end of the 18th century, we began developing many other forms of heating systems that are found in homes around the world today. There are furnaces, boilers, radiant wall heaters, radiant heated flooring, and other styles of heating. For the life of me, I cannot figure out how some of these HVAC units work. Now, I understand the basic concept of how heating systems work. There is a fuel that causes a fire to be heated up. The heat either is forced into the air of your home through HVAC ducts using a blowing motor, or steamed water is forced throughout pipes in your home that is radiated throughout the house. However, these new heating systems have so many working portions and technical parts that I cannot understand them. I hate things that I cannot understand, and HVAC units are no exception. That is why I have decided to stick with my wood-burning heating system. I would rather use a heating system that I understand than break a heating system that I don’t really understand.

Gas fireplace