The Toyota Prius is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by the Toyota Motor Corporation. The EPA and California Air Resources Board (CARB) rate the Prius as among the cleanest vehicles sold in the United States based on smog-forming emissions. The Prius first went on sale in Japan in 1997, and was available at all four Toyota Japan dealerships, making it the first mass-produced hybrid vehicle.