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This 1914 Couple Gear Aerial Ladder Truck is an early example of a hybrid vehicle. Photo: Courtesy of Walter McCall.

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This 1921 Owen Magnetic Model 60 Touring uses a gasoline engine to run a generator that supplies electric power to motors mounted in each of the rear wheels.

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The Honda Insight was the first gas-electric hybrid production vehicle to be sold in the United States.

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Toyota's Prius was the first mass-produced gas-electric hybrid in the world, reaching the Japanese market in 1997.

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The Ford Prodigy is a hybrid electric family car prototype that was supposed to be able to achieve more than 70 miles per gallon fuel economy. It was shown at the 1999 Detroit Auto Show.

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Many years before hybrid trucks like the Silverado Hybrid were on the road, thousands of electric trucks and delivery vehicles were used in major cities in the U.S. and Europe between 1900 and 1920.

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Pay the "Piper?" Almost a hundred years after American engineer H. Piper filed a patent for a gasoline engine-electric motor powertrain, Ford introduced the Escape Hybrid in 2004.