Hard facts

Tom's Hardware has published a detailed report on his visit to Seagate's Northern Ireland-based factory.

His read/write head statistics make fascinating reading:

With a width of less than a hundred nanometers and a thickness of about ten, it flies above the platter at a speed of up to 15,000 RPM, at a height that’s the equivalent of 40 atoms.

If the read/write head were a Boeing 747, and the hard-disk platter were the surface of the Earth, the head would fly at Mach 800, at less than one centimeter from the ground, and count every blade of grass in Ireland, making fewer than 10 unrecoverable errors.
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