The tar (tape archive) command bundles a bunch of files together and creates an archive (commonly called a tar file or tarball) on a tape, disk drive, or floppy disk. The original files are not deleted after being copied to the tar file.
To create an archive using tar, use a command like this, which bundles all the files in the current directory that end with .doc into the alldocs.tar file:
tar cvf alldocs.tar *.doc