Just type man tar in the terminal for the tar command manual.

The meaning of -xvzf is

-x --extract = extract files from an archive
-v, --verbose = verbosely list files processed
-z, --gzip = gzipped files eg. for tar.gz packages
-f, --file ARCHIVE = use archive file or device ARCHIVE

If you have two zip files a.zip and b.zip in your current directory, then

$ cp *.zip destination/

expands to

$ cp a.zip b.zip destination/

The semantics for cp is to copy both a.zip and b.zip to destination.

If you type

$ cp \*.zip destination/

it simply "expands" to

$ cp '*.zip' destination/

i.e. it will try to copy a single file named "*.zip" to destination, which is not what you want.

On the other hand if you type

$ unzip *.zip -d destination/

it will again expand to

$ unzip a.zip b.zip -d destination/

The semantics for unzip is to find a file named "b.zip" inside the archive "a.zip", which is again not what you want.

If you type

$ unzip \*.zip -d destination/

the unzip command does not simply try to unzip the file called *.zip but it will unzip all files ending with .zip.

The difference is that both commands interpret their arguments differently.

Type man tar for more information, but this command should do the trick:

tar -xvzf community_images.tar.gz

To explain a little further, tar collected all the files into one package, community_images.tar. The gzip program applied compression, hence the gz extension. So the command does a couple things:

• f: this must be the last flag of the command, and the tar file must be immediately after. It tells tar the name and path of the compressed file.
• z: tells tar to decompress the archive using gzip
• x: tar can collect files or extract them. x does the latter.
• v: makes tar talk a lot. Verbose output shows you all the files being extracted.

To extract into a custom folder, add the -C option with a folder name of your choice:

tar -xvzf community_images.tar.gz -C some_custom_folder_name

According to http://www.manpagez.com/man/1/unzip/ you can use the -o option to overwrite files:

unzip -o /path/to/archive.zip

Note that -o, like most of unzip's options, has to go before the archive name.

If the unzip command isn't already installed on your system, then run:

sudo apt-get install unzip

After installing the unzip utility, if you want to extract to a particular destination folder, you can use:

unzip file.zip -d destination_folder

If the source and destination directories are the same, you can simply do:

unzip file.zip