CALLERID
Caller ID
Caller ID, also called calling line identification, calling number delivery, calling number identification or calling line identification presentation, is a telephone service, available in analog and digital phone systems and most voice over Internet Protocol applications, that transmits a caller's number to the called party's telephone equipment during the ringing signal, or when the call is being set up but before the call is answered. Where available, caller ID can also provide a name associated with the calling telephone number. The information made available to the called party may be ...The above text is a snippet from Wikipedia: Caller ID
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