UUCP (UNIX to UNIX Copy Program) is an asynchronous terminal line-based system providing support for file transfer and remote execution between different computer systems. These primitive operations are then used to construct a mail system, which is also, confusingly, known as UUCP. Although UUCP was originally developed for use with the UNIX operating system, versions of UUCP are available for other operating systems, including OpenVMS.
PMDF for OpenVMS includes support for Encompass UUCP.

PMDF's UUCP support conforms with RFC 976, "UUCP Mail Interchange Format Standard", authored by Mark Horton. A copy of RFC 976 may be found in the RFC subdirectory of the PMDF documentation directory, PMDF_DOC:[rfc] on OpenVMS or /pmdf/doc/rfc on UNIX.

The following sections describe how to set up PMDF channels for use with UUCP. Familiarity with the basics of UUCP networking is assumed; on OpenVMS systems, familiarity with Encompass UUCP is also assumed.