A kind of little car may someday take the place of today's big ones. If people drive such cars in the future, there will be less pollution in the air. There will be more space for parking in cities. The streets will be less crowded. And driving will be safer as these little cars can go only 65 km per hour. The future cars will be fine for getting round a city, but they will not be useful for long trips. Little cars will go 200km, before needing to stop for more gas. If big cars are still used along with the small ones, two sets of roads will be needed in the future. Some roads will be used for the big fast cars and other roads will be needed for the slow and small ones. It's said that three such little cars fit in the space now needed for one car the usual size.