Gas engines are machines that convert the energy from burning fuel, typically gasoline, into mechanical energy. They work by igniting a mixture of air and fuel in a cylinder, which pushes a piston. This movement is then transformed into rotational energy to power vehicles or machinery. These engines are commonly found in cars, lawnmowers, and generators. They are known for their efficiency and ability to provide quick power. However, gas engines also produce emissions, which can contribute to air pollution, leading to a growing interest in alternative energy sources like electric engines and hybrid vehicles.