Fuel economy refers to how efficiently a vehicle uses fuel to travel a certain distance. It is usually measured in miles per gallon (MPG) or liters per 100 kilometers (L/100 km). A higher fuel economy means that a vehicle can travel farther on less fuel, which can save money and reduce environmental impact. Factors affecting fuel economy include the vehicle's design, engine type, and driving habits. For example, hybrid vehicles often have better fuel economy than traditional gasoline-powered cars due to their ability to use both electric and gasoline power. Regular maintenance, such as proper tire inflation, can also improve fuel efficiency.