Marine propulsion refers to the methods and systems used to move ships and boats through water. The most common types of marine propulsion include diesel engines, gas turbines, and electric motors. These systems convert fuel or energy into mechanical power, which drives the vessel's propeller or water jet, enabling it to navigate. In addition to traditional engines, some vessels use renewable energy sources like wind or solar power for propulsion. Advances in technology are also leading to the development of hybrid systems that combine different power sources, aiming to improve efficiency and reduce environmental impact in marine transportation.