How did ancient Greeks build a mechanical computer 2,000 years before the digital age?

The answer

The Antikythera mechanism, recovered from a Roman-era shipwreck near the Greek island of Antikythera in 1901, dates to approximately 150–100 BCE. It contains at least 30 meshing bronze gears and could predict solar and lunar eclipses, track the positions of the five known planets, and even calculate the dates of the ancient Olympic Games. X-ray tomography by the Antikythera Mechanism Research Project in 2006 revealed inscriptions describing its functions across 3,500 characters. Nothing of comparable complexity appeared in Europe until medieval astronomical clocks some 1,400 years later. Its creator remains unknown, though some scholars link it to Archimedes' workshop tradition.