North American Numbering Plan

High school (ages 12+)
People & Society

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/north-american-numbering-plan

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the international standard compliance?Conforms with ITU Recommendation E.164 for international numbering frameworks
2. What is the historical development?Devised by AT&T in the 1940s for Operator Toll Dialing
3. Why did the North American Numbering Plan start?It began in the 1940s because long‑distance calls were slow and expensive. By giving every region a standard code, people could dial long‑distance calls directly without an operator.
4. How do phone numbers in the NANP look?A NANP phone number has a three‑digit area code, then a three‑digit central office code, and finally a four‑digit station number. For example, 212‑555‑1234.

Numbering Plan Area (NPA): A geographic territory within the NANP designated by a three-digit area code, forming a distinct numbering zone.
Central Office Code: The three-digit prefix within a seven-digit local telephone number that identifies a specific telephone exchange.
Public Switched Telephone Network (PSTN): The global network of circuit-switched telephone networks that enables voice communication via interconnected telephone lines and systems.
ITU Recommendation E.164: An international standard that defines the numbering structure for the world's public telecommunications numbering plans.