The Toyota Prius has become one of the best-known hybrid cars since its debut in Japan in 1997. Here, the components of a Prius are on display at the 2004 Greater L.A. Auto Show.
A new Toyota Prius is seen at Grossinger Toyota on Oct. 13, 2005 in Lincolnwood, Ill. The Prius made the U.S. government's list of most fuel-efficient vehicles in 2005.
A power cord is seen plugged into the bumper of a plug-in variant of the Toyota Prius at the 2008 Plug-In Conference and Exposition in San Jose, Calif. The three-day expo featured industry speakers and exhibitors showcasing technological advancements in plug-in hybrid electric vehicles (PHEV's).
Four generations of the Toyota Prius have rolled out since its debut. This fourth-gen 2010 Toyota Prius is on display during a press preview for the North American International Auto Show in Detroit, Mich.
A logo is seen on a brand-new Toyota Prius hybrid car on display at Marin Toyota in San Rafael, Calif., in March 2009. U.S. gas prices dropped to an average of $2 per gallon in the spring of 2009, and consumer interest in hybrid cars dropped along with it.
A worker polishes a Prius at the AMI 2009 International Auto Fair on March 26, 2009 in Leipzig, Germany.
A view of a third-generation Prius engine is shown during a press conference in Tokyo, Japan. The list price of the third generation Prius starts at $22,000.
A man inspects the engine of a third-generation Prius on May 18, 2009 in Tokyo, Japan. The third-generation Prius added an all-electric compressor for the car's air conditioning system.
Attendees at Mega Web in Tokyo, Japan, explore the interior of a third-generation Toyota Prius. The third-generation Prius featured improved leg room over previous models.