Gaseous renewable fuel combustion is of primary interest for a range of applications including aircraft engines, ground power engines, reciprocating engines, and industrial furnaces, among others. While much of the combustion science and engineering that are needed to design and operate such devices is well developed and available in modern textbooks, the attainment of even higher efficiencies, greater performance, and reduced emissions for an ever-increasing array of new fuels and fuel blends requires an even deeper understanding of fundamental combustion concepts and the underlying physical and chemical phenomena. In many cases, these fundamental concepts are areas of much recent and ongoing research.  This chapter describes the basic combustion and chemical kinetic properties of the fuels, namely hydrogen, syngas, ammonia, methane, natural gas, and ethanol, considering the flame temperature, ignition delay time, flammability limit, laminar flame speed, and fuel stretch sensitivity.