User Management

• Add a user: sudo adduser username
• Add multiple users: sudo adduser username1 username2 username3
• Delete a user: sudo deluser username
• Delete multiple users: sudo deluser username1 username2
• Change a user's password: sudo passwd username
• Change multiple users' passwords: sudo passwd -e username1 username2

Group Management

• Add a group: sudo addgroup groupname
• Add a user to a group: sudo usermod -aG groupname username
• Add multiple users to a group: sudo usermod -aG groupname username1 username2
• Remove users from a group: sudo deluser username1 username2 -G groupname
• Grant sudo privileges: sudo usermod -aG sudo username

Listing Users and Groups

• List all users: sudo getent passwd
• List all groups: sudo getent group
• List users in a specific group: sudo getent passwd | grep groupname