Hello everyone, I am a newbie with the linux OS and have been playing around with adding and removing users, after adding a new user, I tried deleting the user using the userdel command without the -r option, using the ls command still shows the user on my PC and if i try to delete the user again, it says such user does not exist even when i use the -r option. What should I do to get rid of the user ? Iam using the Centos Distro. any help will be appreciated

Hello and welcome to LQ! The "-r" option removes the user's home directory along with its mail (see below the lines from the man page). If you have already issued the "userdel" command, the user is not there anymore, so it doesn't have any effect now: what you see with the "ls" command is not the user itself, but its home directory ("ls" lists files, not existing users). If you want to remove the mentioned home directory you now have to do that manually (as root) with the "rm -r" (remove recursively) command. Pay attention to the fact that after you have removed it, the directory and its content are gone, and might be recovered (no guarantee) only by using specific tools.

Thanks @Philip Lacroix I tried using the rm -r command to remove the user home directory but the directory still exists, I am probably getting something wrong, the recursive remove does not seem to be doing the job for me.

Can you post the exact command you're entering and any error messages you might have received? Note that you will generally need to have root priveliges to delete a directory not owned by you. Also, it good to remember that rm is permanent. There's no trash bin like on some other OSes from which you can recover the files. So make sure there's really nothing in that directory that you (or someone else) might want before you delete it. Tools do exist for data recovery, but it's best to not need to use them in the first place!

Please follow btmiller's above suggestions, so that we can help you effectively. If you still have doubts about commands, files, folders and permissions on Linux systems, I recommend you a guide which is worth reading:

Introduction to Linux - A Hands on Guide, by Machtelt Garrels

Needs the command to be issued as the 'root' user; either use sudo or su, to gain 'root', (if using su, don't forget to use 'exit', so that you don't do anything bad accidentally ).