Definition
A diesel engine is an internal combustion engine that uses compression ignition. Unlike gasoline engines, it doesn't need spark plugs; the fuel ignites due to the heat generated by compressing air. Diesel engines are famed for their fuel efficiency and high torque output, making them perfect for heavy-duty applications. Think of it as the weightlifter of engines, strong and reliable under pressure. They're commonly found in trucks, trains, and construction equipment. While efficient, diesel engines face scrutiny for their emissions, leading to cleaner technologies.