OSPF was derived from an early version of the ISIS protocol. A description for this acronym might be determination of optimum path, because this interior gateway protocol actually uses several criteria to determine the best route to a destination. These include cost metrics which factor in such things as route speed, traffic, reliability, and security. There are two ways that routers can learn about route information. These are called static and dynamic routing.
Manual entries placed in a routing table are examples of static routing.
When routes are learned automatically, this is called dynamic routing. Static route - Route that is explicitly configured and entered into the routing table. Static routes take precedence over routes chosen by dynamic routing protocols. Routing tables based on static information could be used to test a particular link in the network or conserve wide area bandwidth. Static routing is also the preferred method for maintaining routing tables whenever there is only one path to a destination as would be the case with a stub network.