Syngas, or synthesis gas, is a mixture of hydrogen and carbon monoxide,[1] in various ratios. The gas often contains some carbon dioxide and methane. It is principally used for producing ammonia or methanol. Syngas is combustible and can be used as a fuel.[2][3][4] Historically, it has been used as a replacement for gasoline, when gasoline supply has been limited; for example, wood gas was used to power cars in Europe during WWII (in Germany alone half a million cars were built or rebuilt to run on wood gas).[5]