Fidonet: Technology, Use, Tools, and History

FidoNet is a store-and-forward email network developed in 1984 that uses modems over the public telephone network, comprising over 20,000 nodes worldwide and originally built on MS-DOS but later ported to multiple platforms including UNIX and Apple systems. The network uses an efficient numeric addressing scheme (zone:net/node format) and implements zmodem-based protocols designed to minimize modem and telephone costs, with email routed through a hierarchical topology and news distributed via an ad hoc acyclic graph. FidoNet includes gateways to the Internet, typically via the uucp network, and maintains a weekly-updated nodelist distributed through regional and continental coordinators.