IP Address
Since IP Addresses are limited, we have various oraganization that control the distribution of IP Addresses and their resources.
IANA (Internet Assigned Numbers Authority) has authority over the IP Address resource and they delegate these resources to RIR (Regional Internet registry) RIR's in turn distribute these IP Address resources to regional entities which include ISP's (internet service providers), organizations and end users.
We have RIR's oraganization according to continents.
RIR : Regional Internet registry oversees allocation and registration of IP Address resources within a particular region of the world, resources include IP Addresses (IPv4 and IPv6) and autonomous system numbers (which are used for BGP routing)
Following RIR's are in operation