An unambiguous domain name that specifies the exact location of a computer within the domain's hierarchy.
The complete domain name for a specific computer, or host, on the Internet. The FQDN consists of two parts: the host name and the domain name. An example is mycomputer.mydomain.com.
A URL that consists of a host and domain name, including top-level domain. For example, www.symantec.com is a fully qualified domain name. www is the host, symantec is the second-level domain, and .com is the top-level domain. An FQDN always starts with a host name and continues to the top-level domain name, so www.sesa.symantec.com is also an FQDN.