Directory assistance

In telecommunications, directory assistance or directory enquiries is a phone service used to find out a specific telephone number and/or address of a residence, business, or government entity.

Directory assistance systems incorporate a wide range of automation to reduce the cost of human operators. Almost all systems use custom database software to locate listings quickly.

Most directory assistance systems use automated readback systems to give out the phone number. This frees the directory assistance operator to move on to another caller as soon as the correct listing is located.

Some systems have "store and forward" technology which records "city and state" the caller is requesting and then plays the city and state speech to the operator before they come online and then say "Residential or business listing?" or simply "What listing please?"

Interactive voice response systems have been added to many directory assistance systems. These complex systems use speech recognition and recorded speech or speech synthesis to handle the entire call without live operator intervention.

Most systems recognize location and listing. If recognition confidence is high, the best result is played to the caller. If confidence is low, the caller's request is played back to a live operator, who locates the correct listing.

In the North American Numbering Plan (covering Canada and the United States), directory assistance may be contacted by dialing 4-1-1 (one of the N11 codes) or to get a listing in a remote or non-local area code, directory assistance is available at 1-area code-555-1212 or online at 411 Directory Assistance

However, a 411 landline call will provide local listings as well as nationwide listings and sometimes international listings.

Most telephone companies permit up to two listings per 411 call. All wireless carriers offer nationwide listings with 411, and some offer additional Enhanced Directory Assistance services. However, wireless numbers for residential customers are not available via 411.

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