A routing protocol is a special type of networking protocol intended for use by routers on the Internet. Three commonly used routing protocols are EIGRP, OSPF and BGP.
Routing protocols define the communication standards between routers, as well as the paths along which those routers deliver data through a network. As routers communicate throughout the network, they continuously build up a store of information regarding the topology of connected networks.
The main purpose of different network protocols is to define the rules and conventions, as different devices communicate throughout the network. Network protocols include support for devices to connect and communicate with each other directly as well as message acknowledgement and data compression abilities.
The term "protocol family" is used to refer to a group of both high- and low-level network protocols working together. The Internet Protocol family bundles together a number of high level protocols, such as TCP, UDP, HTTP and FTP, which are responsible for bridging the gap between low-level protocols that communicate directly with the physical hardware of a device.
The routing protocols also specify how routers in a network report changes. They make the network more dynamic, so routing decisions do not have to be predetermined and static.