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- Alright, we already
talked about it a little bit

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but you can compress your backups.

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By default, backups are not compressed.

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And for compression the
traditional Linux philosophy

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is applied, which is connect
multiple specialized tools

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instead of building the
required functionality

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in all of the tools.

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The only thing that is

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that is included in, in Tar

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is minus z, minus j or minus uppercase J.

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And while using these options,

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the appropriate
compression tool is called.

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So there are three main
compression utilities.

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We've already seen them
in the previous video

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but you can use them
independently as well.

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So gzip is one of them.

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It has been the default
tool for a long time.

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It's fast and also compatible

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to other operating systems.

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You can easily use a gzip compress file

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on windows, for instance.

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bzip2 was later introduced

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and it compresses in a more efficient way.

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And xz is the most
recent trend in backups.

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The compression rate is great

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but it is significantly slower.

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Significantly, it takes double
the amount of time or more.

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Let's figure out how to work with these.

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So we have the different files, right?

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And if I use gunzip

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on a files.tar.gz,

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now what is it going to do?

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Well, we can see what it's going to do.

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It's going to,

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to extract the tarball
from the compressed file

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and it overrides the tarball
that already existed.

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So what is the result?

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We don't have the gz anymore.

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It's really extracted.

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Now let me remove this tarball. Yes.

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And let's do something
like this on a bzip.

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what was the utility? bunzip.

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A lot of step completion

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if you're not sure
about what you are doing

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just type the first couple of

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of letters of the command

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and then you step completion
to quickly verify.

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And then it looks as
if you're really smart

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and if you really know what you're doing.

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So bunzip2,

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of files.tar.bz is doing what?

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Well,

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it's bunzipping.

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There we go.

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We have the tarball back again.

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And once again, I'm going to remove it.

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So last, there is xz.

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xz minus minus help,

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how do we uncompress with xz?

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We use xz minus d for decompress.

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Okay, here we go.

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xz minus d

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on files.tar.xz.

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And as you can see, we
have back our files. tar.

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As you notice, all of
these compression utilities

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are really decompressing,

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so you lose the original compress file.

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And the only thing remaining
is the decompress file

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as you can see here.

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And that's how you can use them.