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In this video I'll tell
you about the root user.

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The root user is
a user that always exists.

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It lives in the Linux
kernel. We call that kernel space.

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And because it lives in the Linux kernel, the root user
needs no permissions to do whatever the root user wants to do.

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Root has kernel
level access, and permissions.

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Are not dealt with
at the kernel level.

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That makes root an unlimited user account, and
using this account should be avoided at all times.

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On modern distributions, the root user often. Doesn'T
even have a password, which effectively disables the user.

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But you could set
a password if you want.

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But don't forget, you
should never login as root.

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Instead use either su, which
is a poor choice in fact,

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or sudo. Sudo is much,
much better. To get root permissions.

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Let me make a drawing so that I can show you a bit about.
Kernel space and user space and the. Way how the Linux operating system is organized.

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In the design of the
Linux operating system there are two

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essential parts and we can
draw a line in the middle.

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The lower part is kernel space, kernel. Space,
which is also referred to as system space.

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This is where the kernel is used.
The heart of the Linux operating system

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and the mission of the kernel is
to address the hardware in your system.

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The kernel is doing
so by using drivers.

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And in this kernel space there is. Also
a user account, and we call that user Root.

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Root is a default user
that exists. On all Linux distributions.

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It's a kernel space user, and as such there are
no limitations for the. Root user, which makes it very dangerous.

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Then we have user space, and
in user space you are going to

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run your applications and your users
are going. To do their work.

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Now, the user space from user space, sometimes you need access to what
the kernel is doing, and that needs to happen in a secure way.

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And that is why on the
boundary between user space and kernel space,

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systems like permissions are used and
interfaces like system calls are provided.

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Now, the interesting thing here is that permissions are
mainly for allowing user space to access parts of kernel

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space, like users who want to access a file.
But if you are the root user, you are beyond

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permissions, and that is why we will see that
if you are root, even if you don't have permissions

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at all, you can read the files anyway,
and that makes this root user so very dangerous.