Gas engines are machines that convert 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 turns the crankshaft, ultimately powering vehicles like cars and motorcycles. These engines are commonly found in many everyday applications, from lawnmowers to generators. They are known for their relatively simple design and ease of maintenance. However, gas engines also produce emissions, which has led to increased interest in alternative energy sources, such as electric engines and hybrid systems.