Hydrogen is a promising alternative to meet the world's energy demand. The most common use in automobiles has been fuel cells. However, there is a promise use in the production of synthetic fuels. Other studies have shown the use of hydrogen as a fuel additive in internal combustion engines. This article aims to present a review of the ways in which hydrogen is used as a fuel source, showing as a replacement option for fossil fuels, reducing the environmental impact and CO2 emissions.