Linux User Information and Management

Display the user and group ids of your current user:

id

Display the last users who have logged onto the system:

last

Show who is logged in and what they are doing:

w
who

Create a group named "developers":

groupadd developers

Create an user account with a comment and create the user's home directory:

useradd -c "John Doe" -m johndoe

Delete user account:

userdel johndoe

Add user account to the developers group:

usermod -aG developers johndoe