National Numbering Plans are systems established by countries to organize and manage telephone numbers within their telecommunications networks. These plans ensure that each number is unique and can be easily dialed, facilitating efficient communication. They typically define the structure of phone numbers, including area codes and the total number of digits. Each country, such as the United States or Germany, has its own National Numbering Plan, which is regulated by a national authority. These plans help prevent number conflicts and support the growth of telecommunication services, ensuring that new numbers can be allocated as demand increases.