This chapter focuses on commercial or rock blasting explosives. Rock blasting demands different types of explosives than bombs and shells. The chapter describes different types of rock blasting explosives and the methods used for conveying them to the blasting site and putting them into the drillhole. It develops an understanding of how and why these explosives are different from explosives intended for military use and from propellants, pyrotechnics, and other energetic materials. The chapter describes the detonation, which is the rapid process by which the explosive's chemical energy is released, and shock waves, by which the chemical reaction is ignited and by which the pressure developed in the drillhole is transmitted into the rock. It devotes to the prediction and determination of the performance of explosives, again with the main emphasis on rock blasting applications.