The Routing Information Base RIB is the location in which all IP Routing information is stored. The RIB is not specific to any routing protocol, rather, it is the repository where all the routing protocols place all of their routes. Routes are inserted into the RIB whenever a routing protocol running on the router learns a new route. When a destination becomes unreachable, the route is first marked unusable and later removed from the RIB as per the specifications of the routing protocol they were learned from. It is important to note that the RIB is NOT used for forwarding IP datagrams, nor is it advertised to the rest of the networks to which the router is attached.
A Cisco router's RIB will contain filtered routes; however, these will never make it to the "Forwarding Information Base", which contains yet a different set of routes.