How is the distribution of IP addresses on the Internet arranged?

• As you already know, all IP addresses on the Internet must be unique. Therefore, we need some kind of organization that will control the distribution of IP addresses.

• There is such an organization, or rather there are several of them. 
IANA - Internet Assigned Numbers Authority is the most important organization that issues ip addresses to RIR - Regional Internet Registries (Regional Internet Registrar), which in turn distributes addresses to LIR - Local Internet Registries (Local Internet Registrar), and it already issues them to end subscribers.

• There are currently 5 RIRs:

    1) American Registry for Internet Numbers (ARIN) — for North America;
    2) RIPE Network Coordination Centre (RIPE NCC) — for Europe, Middle East and Central Asia;
    3) Asia-Pacific Network Information Centre (APNIC) — for Asia and the Pacific region;
    4) Latin American and Caribbean Network Information Centre (LACNIC) — for Latin America and the Caribbean;
    5) African Network Information Centre (AfriNIC) — for Africa and the Indian Ocean region.