REN and RENAME are the same command.
Renames files and directories.
Examples:
ren filewithtpyo.txt filewithtypo.txt
ren *.cxx *.cpp
Links:
$ ren /?
Renames a file or files.
RENAME [drive:][path]filename1 filename2.
REN [drive:][path]filename1 filename2.
Note that you cannot specify a new drive or path for your destination file.