Propulsion systems are essential technologies that enable vehicles, such as rockets and airplanes, to move through air or space. They work by generating thrust, which is the force that propels the vehicle forward. Different types of propulsion systems include jet engines, rocket engines, and electric propulsion, each designed for specific applications and environments. The efficiency and effectiveness of a propulsion system depend on various factors, including fuel type and design. For instance, liquid propellant engines use a combination of fuel and oxidizer to produce thrust, while solid propellant systems rely on a pre-loaded mixture. Understanding these systems is crucial for advancements in aerospace technology.