Distance Vector routing protocols use frequent broadcasts (255.255.255.255 or FF:FF:FF:FF) of their entire routing table every 30 sec. on all their interfaces in order to communicate with their neighbours. The bigger the routing tables, the more broadcasts. This methodology limits significantly the size of network on which Distance Vector can be used.
Routing Information Protocol (RIP) and Interior Gateway Routing Protocol (IGRP) are two very popular Distance Vector routing protocols. You can find links to more information on these protocols at the bottom of the page. (That's if you haven't had enough by the time you get there !)
Distance Vector protocols view networks in terms of adjacent routers and hop counts, which also happens to be the metric used. The "hop" count (max of 15 for RIP, 16 is deemed unreachable and 255 for IGMP), will increase by one every time the packet transits through a router.