How can I compress a whole directory under Linux / UNIX using a shell prompt?

It is useful to backup files, email all files. Technically, it is called as a compressed archive. GNU tar command is best for this work. It can be use on remote Linux or UNIX server. It does two things for you:

1. Create the archive

2. Compress the archive

You need to use tar command as follows (syntax of tar command):
tar -zcvf archive-name.tar.gz directory-name
Where,

• -z: Compress archive using gzip program
• -c: Create archive
• -v: Verbose i.e display progress while creating archive
• -f: Archive File name

For example, you have directory called /home/demo/prog and you would like to compress this directory then you can type tar command as follows:
$ tar -zcvf demo-11-july-2008.tar.gz /home/demo/prog

Above command will create an archive file called demo-1-jan-2005.tar.gz in current directory. If you wish to restore your archive then you need to use following command (it will extract all files in current directory):
$ tar -zxvf demo-11-july-2008.tar.gz

Where,

• -x: Extract files

If you wish to extract files in particular directory, for example in /tmp then you need to use following command:
$ tar -zxvf demo-11-july-2008.tar.gz -C /tmp
$ cd /tmp
$ ls