mv is a utitily to rename or move files or directories, it only physically moves the file when the source file system is different from the destination file system.
Check here the complete man page.
MV(1) User Commands MV(1)
NAME mv - move (rename) files
SYNOPSIS mv [OPTION]… [-T] SOURCE DEST mv [OPTION]… SOURCE… DIRECTORY mv [OPTION]… -t DIRECTORY SOURCE…
DESCRIPTION Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.
Mandatory arguments to long options are mandatory for short options too. --backup[=CONTROL] make a backup of each existing destination file -b like --backup but does not accept an argument -f, --force do not prompt before overwriting -i, --interactive prompt before overwrite --strip-trailing-slashes remove any trailing slashes from each SOURCE argument -S, --suffix=SUFFIX override the usual backup suffix -t, --target-directory=DIRECTORY move all SOURCE arguments into DIRECTORY -T, --no-target-directory treat DEST as a normal file -u, --update move only when the SOURCE file is newer than the destination file or when the destination file is missing -v, --verbose explain what is being done --help display this help and exit --version output version information and exit The backup suffix is ‘~’, unless set with --suffix or SIM? PLE_BACKUP_SUFFIX. The version control method may be selected via the --backup option or through the VERSION_CONTROL environment variable. Here are the values: none, off never make backups (even if --backup is given) numbered, t make numbered backups existing, nil numbered if numbered backups exist, simple otherwise simple, never always make simple backups
AUTHOR Written by Mike Parker, David MacKenzie, and Jim Meyering.
REPORTING BUGS Report bugs to firstname.lastname@example.org.
COPYRIGHT Copyright © 2006 Free Software Foundation, Inc. This is free software. You may redistribute copies of it under the terms of the GNU General Public License http://www.gnu.org/licenses/gpl.html. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO The full documentation for mv is maintained as a Texinfo manual. If the info and mv programs are properly installed at your site, the com? mand
info mv should give you access to the complete manual.
mv 5.97 January 2007 MV(1)
You need write and execute permission for the parent directory, but not for the file to be moved itself
mv archive archive.txt
With this example you will rename the file archive to archive.txt
mv archive.txt /home/user/archives/
This command will move archive.txt to the directory /home/user/archives/ and will have the same original name.
mv -u file1 file2
With this last command, you will prevent that if file2 exists and is newer that file1, the command will not be executed.