How to open or Untar a ".tar.gz" file in Ubuntu ?

Lets say that the name of file is - test.tar.gz

1. From the terminal, change to the directory where tar file is located.
2. Now to extract the file to the current directory , run the command 
 tar -zxvf test.tar.gz

To extract the file to a specific directory , run
tar -C /directory_name -zxvf test.tar.gz

NOTE : The extensions .tgz and .tar.gz are equivalent and both signify that a tar file zipped with gzip.

How to Untar a ".tar" file ?

1. From the terminal, change to the directory where tar file is located.
2. Now to extract the file to the current directory , run the command 
tar -xvf test.tar

To extract the file to a specific directory , run
tar -C /directory_name -xvf test.tar

Tar Usage and Options

• c – create a archive file.
• x – extract a archive file.
• v – show the progress of archive file.
• f – filename of archive file.
• t – viewing content of archive file.
• j – filter archive through bzip2.
• z – filter archive through gzip.
• r – append or update files or directories to existing archive file.
• W – Verify a archive file.
• wildcards – Specify patters in unix tar command.