Universal Naming Convention
UNC
Uniform Naming Convention
(UNC) The type of file system path used in Microsoft Windows networking to completely specify a directory on a file server.
\\servername\sharename
where "servername" is the hostname or IP address of a network file server, and "sharename" is the name of a shared directory on the server. This is related to the conventional MS-DOS "C:\windows" style of directory name. E.g.
\\server1\dave
C:\users\homedirs\dave
on a server called "server1".
It is possible to execute a program using this convention without having to specifically link a drive, by running:
\\server\share\directory\program.exe
The undocumented DOS command, TRUENAME can be used to find out the UNC name of a file or directory on a network drive.
Even Microsoft don't know whether UNC stands for "Universal Naming Convention" or "Uniform Naming Convention", both appear on their website, sometimes withing the same document, but with a preference for "Universal".