SSH : Allow only certain users to log in

There are numerous user accounts that exist in a Linux system. You will not want to allow every user to log in via SSH.
Let's talk about the scenario: I have many users in my Linux box but real person-related users are root, alice and bob. So, to allow only them to connect via SSH, edit '/etc/ssh/sshd.conf' and add the following line at the end of the file:

AllowUsers root alice bob