The Free On-line Dictionary of Computing (30 December 2018):
Universal Naming Convention
Uniform Naming Convention
(UNC) The type of file systempath used in
Microsoft Windows networking to completely specify a
directory on a file server.
The basic format is:
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.
might be set up to point to
on a server called "server1".
It is possible to execute a program using this convention
without having to specifically link a drive, by running:
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".