Add user to a group in Ubuntu

If there are files, directories or peripherals which are required to be shared between multiple users then, it is better to make them a part of the group.

Change Primary group of a user in Ubuntu

Once we change the primary group of a user. The group ownership of all the files in the user's home directory are modified on its own.

Change Group ID of a file or directory in Ubuntu

If we change a Group's ID then, changes in Group ID do not reflect in files created earlier. We need to manually change Group ID of all those files which were part of that specific group earlier.

Change Group name in Ubuntu

We can change Group name in Ubuntu using groupmod command-line utility. A primary group is created with the same name as that of user.

Change Group ID in Ubuntu

If we want to modify our Group's ID for various reasons at later stages. Then, we can do that through groupmod command-line utility. 

Create a group in Ubuntu

What if we want to assign a specific Group ID to our group. Then, we should know that - Group ID (0) is assigned to root group.

newgrp in Ubuntu

If a user is already a part of some secondary group and wishes to access/modify system resources from that secondary group then, use newgrp command.

Benefits of using Group Accounts in Ubuntu

By grouping users, we basically control which users get access to files, directories, peripherals etc.

/etc/group file in Ubuntu

If a user is a part of more than one group. Then, that secondary group information is listed here in /etc/group file.

/etc/passwd in Ubuntu

For every user account created, there is a corresponding single-line entry in /etc/passwd file, which is further divided in seven fields.