Did you know that humans have been using coal as an enery source for thousands of years? Today, the fossil fuels oil and coal provide almost half of the energy used around the world, and Canada has the world's third-largest oil reserves. As our energy needs grow, scientists and other innovators are seeking energy sources and methods that are efficient, sustainable, and environmentally friendly. In this book, you'll examine oil and coal, weigh their benefits and costs, and see both how we are using these fuels now and how oil and coal might fit into our energy future.