Short answers, pulled from the story.
James Watt began tinkering with a broken model of a steam engine in 1763. His modifications to the engine continued for twelve years until 1775. This work ignited the Industrial Revolution by making steam engines efficient enough for widespread factory use.
Etienne Lenoir created the first commercially successful internal combustion engine in 1860. This breakthrough eventually replaced steam as the primary power source for transportation. The Otto cycle introduced in 1877 offered a higher power-to-weight ratio for cars and aircraft.
The Wärtsilä-Sulzer RTA96-C is the largest internal combustion engine ever built. This 14-cylinder, 2-stroke turbocharged diesel engine weighs 2,300 tonnes and produces over 80 megawatts of power. It was designed to power the Emma Mærsk, the largest container ship in the world when launched in 2006.
The physical principle of producing mechanical force through the interaction of electric current and magnetic fields was understood in 1821. Commercial exploitation required efficient electrical generators and distribution networks. Electric motors are ubiquitous today and can convert over 90% of their input energy into useful power.
Exhaust gas from a spark ignition engine consists of nitrogen, water vapor, carbon dioxide, and toxic compounds like carbon monoxide. The widespread use of engines contributes to the global greenhouse effect with carbon dioxide emissions driving global warming. Diesel engines produce greater particulate and nitrogen oxide pollution than gasoline engines.