History of computing hardware

The history of computing hardware spans developments from early devices used for simple calculations to today's complex computers, encompassing advances in both analog and digital technology. The first aids to computation were purely mechanical devices which required the operator to set up the initial values of an elementary arithmetic operation, then manipulate the device to obtain the result. In later stages, computing devices began representing numbers in continuous forms, such as by distance along a scale, rotation of a shaft, or a specific voltage level.

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