Steam Engine

The steam engine — perfected by James Watt between 1763 and 1782 — converted heat energy into mechanical work with unprecedented efficiency and transformed human civilization. By providing a reliable source of mechanical power independent of wind, water, or animal strength, it enabled factories, railways, and steamships that shrank the world and multiplied industrial output a thousandfold. The Industrial Revolution it powered moved hundreds of millions from agricultural poverty into urban manufacturing, raising living standards dramatically while also creating new forms of misery. Steam engines drove the colonial economies of the British Empire and made possible the modern world's infrastructure.