A Fully Qualified Domain Name (FQDN) is the complete address of an internet host or computer that specifies its exact location within the Domain Name System (DNS) . It consists of the hostname and domain name, and it specifies all domain levels, including the top-level domain. The top of the hierarchy in an FQDN begins with the rightmost label, and the length of each label must be between 1 and 63 octets, and the full domain name is limited to 255 octets, full stops included. An FQDN is always labeled in the format of hostname.domain.TLD, where TLD stands for top-level domain. For example, a mail server on the yahoo.com domain might use the FQDN mail.yahoo.com.
FQDNs are useful in connecting to domain services, such as email or file transfer protocol. They are also important for search engine optimization (SEO) as having an FQDN can improve a websites SEO rankings in web browsers. To find an FQDN, you can use the advanced system settings on Windows, or the terminal on MacOS and Linux.
In summary, an FQDN is a complete domain name that specifies the exact location of a computer or host on the internet. It is composed of the hostname, domain name, and top-level domain, and it is useful for connecting to domain services and improving SEO rankings.
