And it ran faster than Windows ...

Ancient computer had "unexpected degree of sophistication"

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The Antikythera Mechanism, sometimes called the world's first computer, has now been examined with the latest in high- resolution imaging systems and three-dimensional X-ray tomography. A team of British, Greek and U.S. researchers was able to decipher many inscriptions and reconstruct the gear functions, revealing, they said, "an unexpected degree of technical sophistication for the period."
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They said their findings showed that the inscriptions related to lunar-solar motions and the gears were a mechanical representation of the irregularities of the moon's orbital course across the sky, as theorized by the astronomer Hipparchos. They established the date of the mechanism at 150-100 B.C.
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Historians of technology think the instrument is more complex than any known device for at least a millennium afterward. The hand-operated mechanism, presumably used in preparing calendars for seasons of planting and harvesting and fixing religious festivals, had at least 30, possibly 37, hand-cut bronze gear wheels, the researchers reported. An ingenious pin-and- slot device connecting two gear wheels induced variations in the representation of lunar motions according to the Hipparchos model of the moon's elliptical orbit around Earth.

The functions of the mechanism were determined by the numbers of teeth in the gears. The 53-tooth count of certain gears, the researchers said, was "powerful confirmation of our proposed model of Hipparchos' lunar theory."