If you're seeing this page it's probably because you selected it from a menu item in your Web browser.
Many modern network devices, such as network printers, home gateways, personal firewalls, network video cameras, etc., include a little embedded web server.
As these devices start to advertise the presence of their embedded web servers using Bonjour, they will automatically show up on your Web browser's "Bonjour" or "Local Network Services" menu.
This lets you discover all the web-enabled devices on your network, without needing to know about them in advance, or configure anything manually.