A routing protocol is the communication used between routers. A routing protocol allows one router to share information with other routers regarding the networks it knows about as well as its proximity to other routers. The information a router gets from another router, using a routing protocol, is used to build and maintain a routing table. 

Examples of routing protocols are:

• Routing Information Protocol (RIP)
• Interior Gateway Routing Protocol (IGRP)
• Enhanced Interior Gateway Routing Protocol (EIGRP)
• Open Shortest Path First (OSPF)

A routed protocol is used to direct user traffic. A routed protocol provides enough information in its network layer address to allow a packet to be forwarded from one host to another based on the addressing scheme.

Examples of routed protocols are:

• Internet Protocol (IP)
• Internetwork Packet Exchange (IPX)

Web Links Introduction to Routing http://www.cisco.com/ networkers/ nw99_pres/301.pdf