Description
In a hard drive, the heads 'fly' above the disk surface with clearance of as little as 3 nanometres. The "flying height" is constantly decreasing to enable higher areal density. The flying height of the head is controlled by the design of an air-bearing etched onto the disk-facing surface of the slider. The role of the air bearing is to maintain the flying height constant as the head moves over the surface of the disk. If the head hits the disk's surface, a catastrophic head crash can result.
Read more about this topic: Disk Read-and-write Head
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—Ludwig Wittgenstein (1889–1951)
“Everything to which we concede existence is a posit from the standpoint of a description of the theory-building process, and simultaneously real from the standpoint of the theory that is being built. Nor let us look down on the standpoint of the theory as make-believe; for we can never do better than occupy the standpoint of some theory or other, the best we can muster at the time.”
—Willard Van Orman Quine (b. 1908)
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—Ralph Waldo Emerson (1803–1882)