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While creating users and groups,
different properties can be managed.

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Users and their properties are stored in
etcpasswd and common properties that you will

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find are the user id. Every
user has a unique numeric user id.

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The gid in etcpasswd is
the ID of the primary group.

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In passwd, there is only space to hold
one group membership and that's the primary group.

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Then there is the GCOS field, which
stands for General Electric Common Object subscription.

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That's a definition that dates back to the
1970s. Nowadays, mostly we talk about comment field

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and that is an optional description field for
the user where you can enter additional information.

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The home directory refers to the default
home directory where the user will land after

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logging in. So that will be the
default environment where user has write permissions.

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And shell is a program
that is started after user login.

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Now, if you want to list current password
properties for a user, you can use grep on

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the username on etcpasswd. Alternatively, you can also
use getint, which will print these properties as well.

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Passwords are not stored in etcpasswd. They are stored
in the etc shadow command, which we will cover later.

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If you want to change any
of the properties for users, you use

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usermod and passwd. Usermod is for
the generic properties in etc. Passwd and

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passwd is for the password
which is stored in etc shadow.

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Let's have a quick
look before moving on.

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So just one line from etc passwd last
line and this is a line for user Anna.

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So first field username, third field user id.
Then we get the group id. The GCOS field

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is empty, we do refer to home
anna and bin bash is the default shell.

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So what would happen if
we use get and Anna?

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Well, get and is giving me an
error message, and that is because it doesn't

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know about the database. Getent needs us
to specify where we want to get the

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information from and what do we
see? We see the exact same information.

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The interesting thing about getent is not
to get information out of passwd, but if

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ever your users are defined in an
external system such as an LDAP server, GetAndPassWD

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will also get the user information out
of the external system. And that is why

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getent in some environments might be useful.
Anyway, let's talk about groups a little bit.

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So groups are stored in the file etc. Group,
and users that are a group member as a secondary

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group are also administered in etc group. That's because
in etc passwd there's only place for one group membership.

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So that means that you need to get
your group information out of two different files.

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Now, managing group properties is simple.
Groups don't have any significant other properties.

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So the most important thing is to find
the groups that the user is a member of.

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And that's what you can do using the ID command that
we have already seen a couple of times in this video course.