RIR
"A regional Internet registry (RIR) is an organization overseeing the allocation and registration of Internet number resources within a particular region of the world." (Wikipedia) There are 5 RIRs in the world, with AfriNIC being the one for Africa region.
RIRs function in a system of global internet management with IANA and ICANN.
Reference
Wikipedia, "Regional Internet registry," http://en.wikipedia.org/wiki/Regional_Internet_registry