A spark plug is a small device found in the engines of many vehicles, including cars and motorcycles. Its main job is to create a spark that ignites the air-fuel mixture in the engine's combustion chamber. This ignition is crucial for the engine to run smoothly and efficiently, providing the power needed to move the vehicle. When a spark plug wears out or becomes dirty, it can cause problems like misfiring or reduced fuel efficiency. Regular maintenance, including checking and replacing spark plugs, is important for keeping your vehicle in good working condition and ensuring a longer lifespan for the engine.