Rocket systems are vehicles designed to propel themselves into space or through the atmosphere using controlled explosions. They work by expelling gas at high speed from their engines, creating thrust that pushes the rocket in the opposite direction, based on Newton's Third Law of Motion. These systems can vary in size and complexity, from small model rockets to large spacecraft like the SpaceX Falcon 9. Rocket systems typically consist of several key components, including the propellant, which fuels the rocket, and the payload, which is the cargo or instruments being transported. They can be used for various purposes, such as launching satellites, conducting scientific research, or sending humans to space, as seen in missions by NASA and other space agencies.