In recent years, there has been much concern about the world's reliance on nonrenewable resources, such as oil. Scientists are attempting to decrease our dependency on oil--something cars require to work. Hybrid cars, which run on alternative energy sources like sunlight, corn, and biofuels, may be the key to using less oil. How Do Hybrid Cars Work? discusses how these machines work, the science behind the energy they make, and what the use of hybrid cars means for the planet. Full-color photographs and illustrations keep young readers enthralled in the science behind hybrid cars.