Question

how any hard disc work​

Answer 1

The hard drive contains a spinning platter with a thin magnetic coating. A "head" moves over the platter, writing 0's and 1's as tiny areas of magnetic North or South on the platter. To read the data back, the head goes to the same spot, notices the North and South spots flying by, and so deduces the stored 0's and 1's.

~MSD

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