Basic principles including chemical equilibrium, Arrhenius law, and Rankine-Hugoniot relations will be first discussed. Principles of mass diffusion will be discussed and simplified models discussed. The course will then introduce principles of chemical kinetics, and discuss some important chemical mechanisms including the H2-O2 system, and the Zeldovich mechanism for NO formation. Multi-component conservation equations with chemical reaction will be introduced. Various characteristics of premixed and diffusion flames will be studied which covers flame structure, flame stability, flame stabilization, flammability limit, quenching distance and thermal explosion. Combustion phenomena in gas turbines, gasoline engines, diesel engines and power plants will be discussed.