It would be http://name./ as FQDN, but the variant without the . typically works in browsers, too.

The hostname's first n segments, starting from the right (the TLD).

It’s kind of like putting a SIM card in a cell phone – the SIM card tells that phone, “Hey, you work with this particular phone number now.” Just like you can switch out a phone’s SIM card and make the phone work with a different phone number, your domain can be set to work with a different web hosting service.