OSPF stands for Open Shortest Path First, and it is an interior gateway and routing procedure for Internet Protocol networks. It links all the members of a network and reflects changes made by one member to all. These "link states" preserve various amounts of network information.
OSPF uses IP address information to map the visible network. It relays information by using an algorithm to calculate the shortest possible pathways for the structure it is going to create and reflects the changes in network topology to the other members of the network. This information consists primarily of routing tables and is more efficient than other methods that calculate every change instead of the shortest paths.