Whois

Want to find out who owns a domain? Use the WHOIS function. This command allows you to search a database of all of the domains which have been registered. Most WHOIS functions only support the standard top level domains (.NET, .COM, .ORG, .MIL and .EDU), but the function on this page has been expanded to support over 100 different country codes as well.

A wonderful WHOIS system is whois.sc, give them a try.

A few years ago, getting the WHOIS information was very simple. You just asked the central WHOIS database for what you needed, and you got it. Nothing to it. This retuned all of the contacts, including administrative, technical and billing, and the nameserver data.

The problem with this old method was that it allowed for only one domain registrar - Network Solutions. And as long as there was only one it worked fine. 

Now with the decentralization of domain name registrars, all of this has changed. A much more complex, yet more flexible and scalable system has been put in place which allows for multiple domain registrars.

The InterNIK WHOis database still contains a list of all of the .COMs, .NETs and .ORGs. However, instead of containing the actual information, the database contains a pointer to the server of the registrar who maintains the information. So in order to get the WHOis data, you now have to ask InterNIK for the registrar, then ask the registrar computer for the information.

As an added wildcard in the picture, many of the WHOis databases are not updated in real time. So there may be a slight (1 to 3 day) delay until changes are updated.

Some registrars do the favor of looking up WHOis data on other registrar machines for you. Thus, if you ask registrar A for the WHOis data for a domain and it is actually on the computer of registrar B, A may or may not return the data for you, depending upon how the server is configured.

Other domains, such as the country codes, .MIL, .EDU and so on, are handled by their own unique WHOis databases.