Every file in Linux has an ownership. The root user, equivalent to Admin in MS Windows, can access all of them and alter the ownership to any ordinary user.
Thus one can log in root and change the file ownership. Vista and XP operate the same tactic, in the name of security.
While in root this command shows the filing ownership of user Anybody (UID and group details)
Code:
cat /etc/passwd|grep Anybody
To change a directory /mnt/sdb1 for user Anybody this command can be used
Code:
chown -R Anybody /mnt/sdb1
The ownership feature of Linux is one of the weapon in security so that intruder cannot damage files outside the user whose security has been breached. It is a bit of pain in the arXe at first but it does make Linux less prone to attack.