Fossil fuels, including coal, oil, and natural gas, are formed from the remains of ancient plants and animals. Over millions of years, these organic matter decomposes and is subjected to high pressure and temperature deep within the Earth's crust. This process, known as diagenesis, converts the organic material into hydrocarbons, which make up fossil fuels. Coal, for example, is primarily formed from the remains of plants that lived in swamps and marshes millions of years ago. As these plants died and accumulated in these wet environments, they were eventually buried by sediment and subjected to geological processes that transformed them into coal. Oil and natural gas, on the other hand, are formed from the remains of marine organisms, such as plankton and algae, that lived in ancient oceans. Over time, these organic matter was buried and compressed in sedimentary rocks, resulting in the production of oil and gas reservoirs. Understanding the formation of fossil fuels provides insight into their finite nature and the importance of transitioning to renewable energy sources. By studying the geological processes involved in fossil fuel formation, geologists can better predict and locate potential reserves, as well as explore alternative energy options to mitigate the environmental impact of burning fossil fuels.