An archiving utility. Basically, tar is used to build an archive file (usually in .tar file extension, though not absolutely required) from one or more files and directories.
tar cf /tmp/`whoami`.tar ~
Your archive will be located in /tmp/yuni.tar if your username is yuni. To make sure your archive is sane, check by:
tar tvf /tmp/`whoami`.tar
A complete table of content of the tar file will be generated successfully. An insane tar file will also be able to give a table of content, but a partial one. Note the presence of error message similar to the following at the end:
-rw------- yuni/yuni 215245 2001-06-29 16:31:02 ./.bashrc -rw------- yuni/yuni 215245 2001-06-20 08:15:56 ./.bash_profile tar: 509 garbage bytes ignored at end of archive tar: Error exit delayed from previous errors
If this message appears, your tar file is not sane. Do it again. When making tar file, do not change/updated the source files/directories including adding and removing files. A very common mistake for user new to using tar is to create the tar file in the directory they are going to archive: tar cf ./my_archive.tar .