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In this video I want
to tell you about users.

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A user on Linux is an entity that is used
to grant permissions to specific parts of the Linux operating system.

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And there
are pretty essentials.

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Users are used mainly by
services on the Linux operating system.

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And running services with a restricted user account avoids
running them with too many permissions as the root user.

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So you'll find that
many server specific users exist.

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People users on Linux are mainly used
for IT staff as end users don't

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normally log into Linux directly, but rather
to the applications that they are using.

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So on a normal Linux system
you won't find too many users.

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Let me show you how these users occur
on things that you are doing on Linux.

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So when I type psaox for
instance, then we can see all

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processes within the first column the
user that has started the process.

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Now I'm not interested in root and student, I'm interested
in SSSD right here. That's one of the system users.

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And if we scroll up a bit we
should see more of these system users like

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rtkit and like callord. These are user accounts
that have been created for these specific services.

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They are stored in the
file etcpasswd and they are the

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users that you will find
on top of the file.

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Now what do we find in this file? Now
that we are at it, let's talk about it.

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So here highlighted we have the LP users different
field. First field has the name of the user.

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Then we have an X that's a placeholder
where in the past an encrypted password was stored.

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Now we have the four which is the unique user id and
the seven which is the group that the user is a member of.

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Then LP
is full name.

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This is what we are talking about. The home directory is
set to var spool LPD and the default shell for this user

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is set to user has been no login which is good
because you don't want these system users to be ever logging in.

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Now of course you don't have to
remember all of this. Man 5 on

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passwd is giving the man page for
etc where all this information is documented.

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LS L also
shows user related information.

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So here we have that LS L where we can see that all vals
have a user that is owner as well as a group that is owner.

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In later videos you'll learn how these ownerships
are used for granting permissions to your users.