Direct Distance Dialing

Direct distance dialing (DDD) 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 (IDDD).

DDD is a North American Numbering Plan term considered obsolete since completing a call in any manner other than direct dialing became rare. In the United Kingdom and other parts of the Commonwealth of Nations, the equivalent terms are or were "STD", for subscriber trunk dialing, and "ISD" for international subscriber trunk dialing.

Read more about Direct Distance Dialing:  History, Hardware, IDDD

Famous quotes containing the words direct, distance and/or dialing:

    He had robbed the body of its taint, the world’s taunts of their sting; he had shown her the holiness of direct desire.
    —E.M. (Edward Morgan)

    From a distance the rushing of the torrent delights and uplifts us, but it rocks us in a flimsy boat, we are overwhelmed by despair. The same applies to danger.
    Franz Grillparzer (1791–1872)

    Although I will inherit darkness
    I will keep dialing left to right.
    I will struggle like a surgeon.
    I will call quickly for the glare of the moon.
    I will even dial milk.
    Anne Sexton (1928–1974)