Computer disk drives have come a long way since they were invented in the 1950's. The technology has been improved remarkably over the years. However, the fundamental principle behind how hard disks work is basically the same. A platter with a magnetic surface spins while an electronic component called a "head" is positioned over areas of the platter to read and write data. It is very similar to the old phonograph with an arm and a needle picking up music from the tracks on the record. Hard disks spin much faster than a phonograph record and the head does not actually touch the platter. However, the head is positioned very close to the spinning platter. Early hard drives would frequently suffer a mechanical failure that would allow the head to actually touch the surface of the spinning platter, which would cause a horrendous noise as the head was destroyed while it cut grooves into the platter. The term "crash" was a reference to the read/write head physically crashing into the rapidly moving platter.

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