Name server lookup is a tool used to learn information concerning a domain by querying DNS. DNS is the service that allows IP addresses to be translated into human-readable web links such as google.com. When entering a domain name, such as nslookup microsoft.com A response will come in giving the IP Address and other information of a domain. A reverse dns lookup can be done by giving the ip address as an arguement instead of the translated address, and the translated address will be given in return. .
In the example above, the user wishes to lookup the domain information of rit.edu. The system looks in its records and retrurns a non-authoritative answer concerning the server and address information. This is very useful when troubleshooting address-related issues.