An outboard engine is a type of propulsion system used on boats, mounted externally at the rear. It combines the engine, gearbox, and propeller into a single unit, making it easy to install and remove. Outboard engines are popular for their versatility, as they can power various types of boats, from small fishing vessels to larger recreational crafts. These engines come in different sizes and power ratings, typically measured in horsepower. They can be powered by gasoline or electric sources, with modern models offering improved fuel efficiency and reduced emissions. Outboard engines are favored for their maneuverability and ease of maintenance, making them a practical choice for boaters.