If your system administrator has UUCP (UNIX-to-UNIX Copy Program) set up to communicate with remote sites, you can use this facility to send or retrieve files, or to run commands or custom applications at other sites in the UUCP network. To send or retrieve files from remote sites, use the uucp command; this causes a file transfer request to be queued. Depending on how your system is set up, a file transfer request may be processed immediately or later at a scheduled time.

UUCP provides the uucp command, which schedules files to be exchanged with other UUCP systems, and the uux command, which schedules commands to be executed by other UUCP systems. However, the uucp and uux commands do not cause any files to be exchanged or commands to be executed. For this, UUCP provides two daemons called uucico and uuxqt, which establish communication sessions, transfer data, and execute commands according to the requests scheduled by uucp and uux.