The fossil fuel formed from ancient plant material is coal. This combustible sedimentary rock originates from the remains of plants that accumulated in swampy environments millions of years ago. Over time, heat, pressure, and geological processes transformed these organic materials into coal through a process known as coalification. Coal is primarily used as a fuel source for electricity generation and various industrial processes. However, its extraction and use raise significant environmental concerns regarding air pollution, greenhouse gas emissions, and habitat destruction.