Basic Security Defaults to adjust in an Ubuntu installation

clipped from help.ubuntu.com Unsafe Defaults While Ubuntu comes secure and ready to use, many people decide to offer other services on their computer, such as running a FTP server or Apache. The purpose of this page is to advise these users on the settings that they should probably change. Shared Memory SSH Default Settings SSH Root Login SSH Login Grace Time SSH Welcome Banner SSH Allowed Users "su" program available to non-admin users