Fully qualified domain name
A Fully qualified domain name (FQDN) is a string of characters which identify a specific host using DNS servers. It includes the top-level domain (TLD), domain name, and subdomain or hostname. Each portion is separated from the others with a period.[1][2]
Examples
Consider this web address: www.example.com
The last set of digits takes priority, so the "com" is considered first. It refers to the ".com" DNS registry, as being the place where more information can be found. When attempting to connect to this website, the web browser in this case will contact the "com" DNS servers for more information. A "com" DNS server will then be asked about "example". The DNS server will return the public IP address of the main "example" server. Now the web browser contacts the "example" server using the IP address it just received from the DNS, and ask for "www". The "example" server will then pass off the browser to the "www" host, which in this case is serving the main website.[1][2]
In an internal network, a FQDN might look a bit different, like: workstation16.dev.companyname
In this case, attempting to connect to this address will start with "companyname". Here, the system will presumably find a DNS server, which can then be asked for information on "dev". The visitor is provided the IP address of "dev", and connects to that. Now it asks for "workstation16", which in this case would probably be a file directory belonging to an employee's computer.
