An internal combustion engine (ICE) is a heat engine in which the chemical energy of a fuel that burns in the working cavity is converted into mechanical work.

They created an internal combustion engine in the middle of the 19th century, when the steam engine reigned supreme in the transport. At that time, illuminating gas was used to illuminate the streets. The property of new fuel prompted the inventors to the idea that the piston in the cylinder can move not the steam, but the gas mixture. Another technical achievement helped answer the question of how to ignite this mixture — an induction coil for producing an electric spark.

The first practically suitable gas d. with. was designed by French mechanic Etienne Lenoir (1822–1900) in 1860. The efficiency of this engine was only 3.3%. In 1876, the German inventor Nikolaus August Otto (1815–1891) built a more sophisticated 4‑stroke gas d. In. With. Compared with the steam engine installation D. century. With. In principle, it is simpler, since one link of the energy conversion — the steam boiler unit — has been eliminated. This improvement led to a more compact D. in. c., lower mass per unit of power, higher efficiency, but it required better quality fuel (gas, oil).

In the 1880s O.S. Kostovich in Russia built the first gasoline carburetor engine. In 1897, German engineer Rudolf Diesel (1858–1913) received a patent for an engine, later named after him. He, working to improve the efficiency of D. c. s., proposed compression ignition engine. The improvement of this is at the L. Nobel plant in St. Petersburg (now Russian Diesel) in 1898Ц99 allowed to use oil as fuel. As a result of this D. in. wWith becomes the most economical stationary heat engine. In 1901, the first tractor was developed in the USA from the D. century. wWith Further development of automobile D. century. wWith aAllowed he brothers O. and W. Wright to build the first aircraft from the D. in. C. Despite the obvious advantages of the internal combustion engine, until the end of the 19th century, steam and electric were considered more promising than gas and gasoline. In the USA, for example, from those issued by 1899. 40% of the mechanical crews were paromobili, 38% — electric vehicles and only 22% — gasoline vehicles.