DIRECTDISTANCEDIALING
Direct distance dialing
Direct distance dialing or direct dial is a telecommunications term for a network-provided service feature in which a call originator may, without operator assistance, call any other user outside the local calling area. DDD requires more digits in the number dialed than are required for calling within the local area or area code. DDD also extends beyond the boundaries of national public telephone network, in which case it is called international direct dialing or international direct distance dialing .The above text is a snippet from Wikipedia: Direct distance dialing
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