The cu command is used to call up another system and act as a dial in terminal. It can also do simple file transfers with no error checking. . cu is part of the UUCP source but has been split into its own package because it can be useful even if you do not do uucp.
UUCP will copy files to or from another (usually *nix) system, which also runs uucp. . UUCP is used to transfer mail, news and random files between systems which are not connected by more modern networks. The communication can be made via modems, direct (hard-wired) serial connections or via an IP connection.
