Fuel gas is like a gas that makes things go. Just like how we need food to make our bodies go, machines and things that move need fuel gas to work.
Fuel gas is made from things like natural gas, propane, and sometimes even wood or coal. It's usually kept in big tanks or pipes and then delivered to where it needs to go, like a factory or a car.
When we light a fire, we use fuel gas to make it happen. The gas is mixed with air and then it ignites, creating a flame. This flame can be used to cook food, heat water, or even power an engine.
So basically, fuel gas is like a special kind of gas that helps make things move and work. It's kind of like the food that machines need to run!