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- This lesson is dedicated
to the root user.

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Now, what is the root user?

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The root user is the
almighty administrator user.

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There are no restrictions
to the root user at all,

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and that makes the root user in Linux

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more powerful than administrator
in a Windows environment,

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for instance,

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because an administrator user

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in a Windows environment
is just a user that has

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all privileges that you can imagine.

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The root user in Linux is living

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in a world where privileges do not apply.

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And this world is called
Linux kernel space.

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The Linux kernel is the
heart of the operating system

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and there are no restrictions

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in what the Linux kernel can do.

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Because it's the heart
of the operating system,

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it needs to be able to do everything.

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And in that environment,

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we need a user and that's the root user.

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So the root user needs no permissions to

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whatever root wants to do.

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And that's because a root
has kernel level access.

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And that makes root an
unlimited user account.

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Using this account should
be avoided for that reason.

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Now, the good thing is

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that recent Linux distributions either

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don't set a password for the root user,

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so you cannot use it,

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or they make enabling
the root user optional,

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so that it's your choice.

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In all the Linux distributions,

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it was common to set a root
password while installing

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and not do anything else.

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So there, it was common to
open a shell as the root user.

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Nowadays, we don't do that anymore.

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The best alternative to
using the root user is

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to use sudo.

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Sudo does require authorization,

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so it doesn't work for any user.

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It only works for authorized users.

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And sudo is what you put
in front of a command.

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We've already seen it a couple of times.

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If you put sudo in front of a command,

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you run that specific command
with super user powers.

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Alternatively, there is also su.

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su can be used to open a root shell

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after logging in as an ordinary user,

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but su is going to prompt
you for the root password and

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how is that going to work if
you don't have a root password?

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Well, it doesn't,

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and that is what makes su of limited use.

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In the next video,

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we will further explore the
use of sudo as well as su.