So I had to do an exercise in a book as homework. First you had to create a user like:useradd -c Steven Baxter -s /bin/sh sbaxterThen you had to add some files to the /home/sbaxter directory:touch /home/sbaxter/ some.txt new.txt files.txtThen you had to remove the sbaxter user and create a new user named mjane. To my suprise when I ran find /home/ -user mjane, the new user mjane now owned all of sbaxter's old files, what happened?
Why did a new user inherit files from a deleted user?
users;administration
The devil is in the details, in the useradd man page (you can see that by issuing man 8 useradd):   -u, --uid UID       The numerical value of the user's ID. This value must be unique,       unless the -o option is used. The value must be non-negative. The       default is to use the smallest ID value greater than or equal to       UID_MIN and greater than every other user.So it will default to using the smallest uid unused, that is larger than other users, in the password file. Seeing as deleting sbaxter removed him from the passwd file, his uid is free and gets assigned to mjane (as the uid useradd picks is the same for both users at the time the useradd command was used). Files on disk only store uid, and NOT the user name translation (as this translation is defined in the password file). You can confirm that by issuing ls -ln to see what uid ownership files have.I would actually recommend you disable rather than delete accounts. Locking accounts on most Linux distributions can be achieved with usermod -L -e today <username>, which locks the password and sets the account to expire today (you can see the expiry date of an account with chage -l).