EIGRP (Enhanced Interior Gateway Routing Protocol) is an advanced distance-vector routing protocol used for automating routing decisions and configuration in computer networks. It uses neighbor discovery processes to dynamically learn about other routers on directly attached networks, reliable transport to guarantee ordered packet delivery, and the DUAL finite state machine to track routes and calculate the best paths. The basic components and packet types of EIGRP, such as hello, update, query, reply and request packets, allow it to share routing information between Cisco routers.