Chemical rockets are devices that use chemical reactions to produce thrust. They typically burn fuel and an oxidizer, creating hot gases that expand rapidly and are expelled through a nozzle. This process generates the force needed to propel the rocket into space. The main components of a chemical rocket include the propellant, which consists of the fuel and oxidizer, and the rocket engine, which facilitates the combustion process. Chemical rockets are widely used in space exploration, including missions by NASA and other space agencies, due to their ability to generate high thrust and lift heavy payloads.