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mv

abbr. 1 (context computing English) a Unix command to move a file 2 millivolt

Wikipedia
Mv

mv (short for move) is a Unix command that moves one or more files or directories from one place to another. If both filenames are on the same filesystem, this results in a simple file rename; otherwise the file content is copied to the new location and the old file is removed. Using mv requires the user to have write permission for the directories the file will move between. This is because mv changes the content of both directories (i.e., the source and the target) involved in the move. When using the mv command on files located on the same filesystem, the file's timestamp is not updated.

On UNIX implementations derived from AT&T UNIX, cp, ln and mv are implemented as a single program with hard-linked binaries. The behavior is selected from the last path component name in argv[0]. This is a common technique by which closely related commands that have been packaged as a unit allow the user to specify the particular course of intended action.