Definition of area code

The concept of assigning unique numerical codes to geographic locations for telephone communication dates back to the 1940s in the United States. Initially, these codes were referred to as "exchange codes" or "central office codes." However, as the demand for telephone services grew and the number of telephone lines increased, it became necessary to divide larger regions into smaller areas to ensure more efficient use of resources. In the 1960s, the first area codes were introduced to cover these smaller areas. The term "area code" was officially adopted by the North American Numbering Plan Administrator (NANPA) in 1967 to simplify and standardize the process of assigning codes. Today, area codes are used throughout North America to ensure uniform and efficient telephone communication across regional boundaries. The NANPA is responsible for managing the North American Numbering Plan (NANP), which includes the administration and assignment of area codes to telephone companies for use in their respective service areas. With the increasing demand for new telephone numbers, the NANPA has implemented several measures to manage the numbering resource, including splitting area codes into smaller geographic areas and implementing ten-digit dialing in some regions.