No other form of energy can do all these things. One of the main tasks of electrical utilities is to convert other forms of energy into electricity. They take forms of energy that are cheap and abundant, but less versatile, such as the kinetic energy of falling water or the chemical energy in coal, and use them to create electricity. The energy resources found in nature are usually more useful to people when they have been converted into electricity. Oil provides liquid fuels that are the energy base for most transportation.
Oil is an effective and convenient fuel for moving vehicles.
The liquid fuel is conveniently stored in a tank and can be easily delivered to an engine without needing bulky batteries or inconvenient piles of coal. It also burns completely without leaving ash behind, as coal does. Since the invention of the internal-combustion engine, and later the jet engine, oil products have become the fuels used to power most of the moving vehicles of the world. The continued use of oil is threatened by its finite supply and by its increasing rate of use. Heat is required for cooking, comfort and many industrial processes.