A Number Resource Organization (NRO) is a group responsible for managing and distributing Internet number resources, such as IP addresses and AS numbers. These organizations ensure that these resources are allocated fairly and efficiently to Internet Service Providers (ISPs) and other entities, helping to maintain the stability and growth of the Internet. The NRO is a collaboration of five regional organizations, including ARIN for North America, RIPE NCC for Europe, APNIC for Asia-Pacific, LACNIC for Latin America, and AFRINIC for Africa. Together, they work to promote best practices in resource management and support the global Internet community.