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Internal combustion engine and the car
engine 1876 (Otto); car 1886 (Benz)· Invention or discovery· Transport & space
Well documentedSolid records, physical evidence or scientific consensus.
Engines that burn fuel inside the cylinder, small and light enough to power a personal vehicle, starting with Otto's engine and Benz's car.
See it on the Technology & Medicine map →How it works
A steam engine burns fuel outside, in a boiler; an internal combustion engine burns it inside the cylinder, so it can be far smaller. Étienne Lenoir ran a gas engine in 1860, and Nikolaus Otto's 1876 four-stroke design (intake, compression, power, exhaust) became the standard. Karl Benz patented a three-wheeled gasoline car in January 1886, and Gottlieb Daimler and Wilhelm Maybach built a motor carriage that year. Bertha Benz's 1888 drive of about 100 km proved it practical.
Why it mattered
The car remade daily life and land use: suburbs, highways, shopping centers and oil geopolitics all follow from it. Its engine also made powered flight possible.
How we know
Benz's German patent 37435 of January 29, 1886, and his Patent-Motorwagen survive. Otto's patent was voided in Germany in 1886 after Alphonse Beau de Rochas's earlier French patent surfaced.
Still unknown or debated
Who 'invented the car' depends on definitions: Cugnot's 1769 steam tractor, Siegfried Marcus's gasoline cart in Vienna (its date is disputed) and Benz all have claims.
Inside this (3)
Connections (6)
▸Gunpowder inspired Huygens's engine, a forerunner of the Internal combustion engine and the carMostly agreed
The connection
In 1673 Christiaan Huygens designed an engine in which a small gunpowder charge exploded inside a cylinder, driving out the air; as the gas cooled, outside air pressure pushed the piston down. It never ran practically, but it was the first plan for burning fuel inside a cylinder, the core idea of the internal combustion engine.
When and how
Paris, 1673, where the Dutch scientist worked for the French Academy of Sciences, with his young assistant Denis Papin, who later turned to steam.
How sure are we?
Huygens described the engine in a 1680 paper. The line to Otto is one of ideas, since 19th-century builders burned gas or gasoline, not gunpowder.
Debates and open questions
How directly Huygens influenced later engine inventors is unclear; Papin's switch to steam suggests the gunpowder engine was a dead end that inspired by example, not design.
▸Internal combustion engine and the car displaced Watt's steam engineWell documented
The connection
Internal combustion engines were smaller and lighter and started quickly, with no boiler to fire up or refill. Over half a century they replaced steam in road vehicles, tractors, ships and, as diesels, railway locomotives. Steam cars such as the Stanley Steamer competed until about the 1920s. Steam survives mainly as turbines in power plants.
When and how
Gradually, about 1900–1970: cars by the 1910s, helped by Charles Kettering's 1912 electric starter; tractors in the 1920s; US railroads by about 1960; Britain's last mainline steam train in 1968.
How we know
Production figures for cars, tractors and locomotives show the switch clearly, and railway and farm-equipment records chart steam's decline decade by decade.
Debates and open questions
Some historians argue steam cars lost mainly to cheap gasoline and Ford's mass production rather than to technical inferiority.
▸Petroleum industry fuelled the Internal combustion engine and the carWell documented
The connection
Refiners first wanted kerosene for lamps; gasoline was a nearly worthless by-product. The car turned it into the main product. Cheap, energy-dense gasoline from booming oil fields helped internal combustion engines beat steam and electric cars. Today road transport uses close to half of the world's oil.
When and how
From the 1900s in the US, Russia and beyond; the Spindletop gusher in Texas (1901) flooded the market with cheap oil just as cars took off.
How we know
Oil-industry and fuel-sales statistics show gasoline displacing kerosene as cars spread. Ford's Model T ran on gasoline, though it could also burn kerosene or ethanol.
Debates and open questions
Historians debate whether electric cars, popular around 1900, lost mainly to battery limits or to cheap oil, Ford's low prices and the 1912 electric starter.
▸Internal combustion engine and the car was mass-produced on the Moving assembly line (Ford)Well documented
The connection
The Model T, launched in 1908, was simple, tough and designed to be built in huge numbers from interchangeable parts. Demand outran Ford's workshops, so his engineers developed the moving line to build it faster. Output rose from under 200,000 cars in 1913 to about 2 million in 1923; over 15 million were made by 1927.
When and how
Ford's Highland Park plant near Detroit; a moving line for flywheel magnetos in April 1913, then the full chassis line by early 1914.
How we know
Ford production records and time studies at the Benson Ford Research Center document each step, with falling assembly times and prices.
Debates and open questions
Whether Ford's $5 day was mainly about cutting worker turnover or about creating customers who could afford cars is debated.
▸Internal combustion engine and the car gave its engine type to The airplane (Wright brothers' first flight)Mostly agreed
The connection
Flight needed an engine powerful for its weight, which steam could not offer. Gasoline engines built for cars and boats came close. The Wrights found no maker willing to supply a light enough one, so mechanic Charlie Taylor built a 12-horsepower engine with an aluminum crankcase in about six weeks, using car-engine ideas. Car makers later built many aircraft engines.
When and how
Dayton, Ohio, winter 1902–03, in the Wright Cycle Company shop; in World War I car makers like Rolls-Royce and Packard built aircraft engines.
How sure are we?
The Wrights' letters record their failed requests to engine makers; the original engine survives with the 1903 Flyer; wartime records show car firms making aero engines.
Debates and open questions
Samuel Langley's rival Aerodrome had a far stronger engine but crashed twice in 1903, so most historians credit the Wrights' control system more than their engine.
▸Internal combustion engine and the car is being electrified by Cheap solar, batteries and electric carsWell documented
The connection
Since Benz's 1886 car, road transport has run mostly on gasoline and diesel, now roughly a sixth of global carbon dioxide emissions. Cheap lithium-ion batteries let electric motors, simpler and about three times as efficient, compete. Electric and plug-in hybrid cars were nearly half of China's new car sales in 2024, steadily displacing combustion engines.
When and how
Electric cars were common in US cities around 1900 before gasoline won; the revival began with Tesla's Roadster (2008), the Nissan Leaf (2010) and Chinese makers such as BYD.
How we know
Sales data from the IEA and national car associations; carmakers' announced phase-outs of combustion models; national emissions inventories.
Debates and open questions
How fast the shift will go outside China and Europe, and whether hybrids, charging gaps or tariffs will slow it, is debated.