Security (Why FreeBSD?)

FreeBSD has a significantly better security record—particularly out-of-the-box security—than most Linux distributions. For example, a default FreeBSD installation includes OpenSSH configured to disallow root logins—a potential attacker must first know the account name of a user in the wheel group (because only users in group wheel can use su), log in as that user, and then su to root. Most Linux distributions instead install OpenSSH configured to allow root logins, which is more insecure because it allows a cracker to use an automated program to attempt dictionary or brute-force attacks against the root account.

Furthermore, because only users in group wheel can su to root, even if a remote attacker knows root's password, the attacker is powerless if he cannot access the account of a user in group wheel.