Hybrid engines combine two power sources, typically an internal combustion engine and an electric motor. This design allows vehicles to use fuel more efficiently, reducing emissions and improving fuel economy. The electric motor can assist the engine during acceleration or operate independently at low speeds, making driving smoother and quieter. These engines can be found in various vehicles, including cars and buses, and are part of the broader trend towards sustainable transportation. By utilizing both gasoline and electricity, hybrid engines help decrease reliance on fossil fuels while promoting cleaner air and reduced environmental impact.