Hydrogen fuel is a type of fuel that is made from hydrogen. Hydrogen is the most abundant element in the universe, and it can be found in many different places, such as water and natural gas. Hydrogen fuel is made by taking hydrogen from these sources and making it into a gas or a liquid by a process called electrolysis. Hydrogen fuel has a lot of energy in it, which can be used to power cars, buses and other vehicles. It also produces very little pollution, which makes it better for the environment.