Fuels are materials that store potential energy, originally only those that release energy through combustion but now also nuclear. The document provides 7 tips to save fuel like carpooling and using public transport. It also lists 5 driving tips to save fuel like driving smoothly and using overdrive. While believing fuel costs will remain high, it suggests getting efficient cars, biking, or working from home but also driving economically. It acknowledges some cars' engines are inefficient regardless of driving style.