How to add and delete group in Linux

In Linux, there are several categories of users that determine the permissions and access levels of files and directories. Below is an option table for some common commands related to file ownership and permissions and some simple examples:

CommandDescriptionExample

chown	Changes the ownership of a file or directory	sudo chown john file.txt (changes the owner of "file.txt" to user "john")
chgrp	Changes the group ownership of a file or directory	sudo chgrp developers file.txt (changes the group owner of "file.txt" to group "developers")
chmod	Changes the permissions of a file or directory	sudo chmod 644 file.txt (sets the permissions of "file.txt" to read-write for owner, read-only for group and others)
umask	Sets the default file permissions for new files and directories	umask 022 (sets the default permissions for new files to read-write for owner, read-only for group and others)
sudo	Executes a command with root user privileges	sudo apt-get update (updates the package manager with root user privileges)

In Linux, the root user is the superuser with full privileges and access to all system resources.