How long ago people used gears?

Answer 1

People have been using gears for thousands of years, with some of the earliest known examples dating back to ancient Greece around the 3rd century BCE. The Antikythera mechanism, an ancient Greek astronomical device, is one of the earliest known gear systems and demonstrates advanced gear engineering. Since then, gears have evolved and been utilized in various applications, particularly during the Industrial Revolution in the 18th and 19th centuries. Today, they remain fundamental components in countless machines and devices.