The physical server's page lists the actual servers that are connected to your OpenVZ Web Panel installation. By default, the first physical server you will see listed is localhost. You can connect more than one OpenVZ server to your OpenVZ installation to manage all of your servers from a single location instead of installing OpenVZ Web Panel on all of your servers that require multiple logins to manage.
Localhost is a subsection of physical servers; this is the first and primary physical server that is connected to OpenVZ Web Panel. At the top of this page, you have two buttons: