Hydrogen fuel cells provide a promising alternative fuel source for automobiles. A hydrogen fuel cell works by splitting hydrogen molecules into protons and electrons, with the protons passing through a membrane to the cathode where they combine with oxygen and electrons to produce water and electricity. This electricity can then power an electric motor in a vehicle. Compared to gasoline engines, hydrogen fuel cells have higher efficiency and produce no emissions other than water vapor. However, challenges remain in developing affordable hydrogen storage and distribution infrastructure comparable to gasoline. With further technological advances, hydrogen fuel cells may become a widely viable eco-friendly transportation solution.