tar is a facility in Linux that creates archived file using a set of files. One file will be created that contains all the files in it. But do not get misunderstand, ".tar" file is not a compressed file. It is only a collection of files within a single uncompressed file.
TAR
1. Create tar archive
$ tar -cf tarFileName.tar file1 file2 file3
This will create an achive named tarFileName.tar and that will include the files specified there (ie: file1, file2, file3).
2. View the list of files
$ tar -tf tarFileName.tar
This will list the details of the files inside the archive.
3. Extract tar archive
$ tar -xf tarFileName.tar
This will extract the archive and create the files that were inside the archive.
The above options have the meanings as:
c - create an archive
f - archive file
t - list the content of the archive
x - extract an archive
GZIP
If the file is a ".tar.gz" or ".tgz" file it is a collection of files that is compressed. To compress a file, first create the tar file then gzip the file. For using gzip the option -z has to be used with the above command.
1. Create tar archive
$ tar -czf tarFileName.tar file1 file2 file3
Now the archive is created as a compressed file.
z - compress using gzip utility