The mechanical clock has no single inventor: its heart, the escapement — the device that releases a gear train in measured ticks — appeared in Europe around 1275–1300, turning falling weights into counted time. China's Su Song had built a giant water-driven astronomical clock tower in 1088; Christiaan Huygens's pendulum clock of 1656 made clocks accurate to seconds a day.
Before the escapement, time was water and shadow: sundials, water clocks, marked candles. The escapement married power to precision — a weight's steady fall chopped into equal beats — and the mechanical clock became the first true machine of the industrial age, centuries before steam.