Dial wiki:
>For other uses, see Dial (disambiguation). In telephony and telecommunications in connection with a telephone, a dial refers, in older telephones, to a rotating disk with 10 numbered finger holes. When a particular numbered hole is rotated with the finger to a finger stop set at a specific point across the dial, then released, the dial mechanism rotates the dial back to its original position and transmits pulses down the telephone line according to the number of the hole selected.
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