Fossil fuels are non-renewable energy resources. That means we can’t reproduce/recycle it. Fossil fuels are formed by decomposition of plants and animals inside Earth for a period of more than 100 million years. There are three type of fossil fuels like Coal, Oil and Natural gas. I don’t want to go deep on why/how these fossil fuels are used, I will just stick on why the combustion of fossil fuels is Evil, IMO.

Fossil fuels generate a huge amount of energy by combustion process. In combustion process, the result will be Energy + Heat (co2). This heat when gone into outermost layers of our atmosphere where ozone is present, it reacts with the ozone

Petrol is like boon to our society. When petrol is combusted, we can produce lots of energy which can be used for many good things like travelling long distances in short time. Travelling in short time is possible by using machines which can combust this petrol (known as Vehicles).