American Telephone and Telegraph establish the Area Code system for World Zone 1 (North America) to allow operators and later automatic switching systems to handle nationwide telephone calls. Previously, telephone calls were partially handled by automatic switching systems but were limited to local calls. Several plans are considered for the approach to numbering, but the deciding plan results in 86 area codes convering the USA and Canada. Soon it is possible to telephone many telephone numbers across the country with no human intervention.

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