This protocol has existed since the inception of the world wide web web, and it is already more than 20 years.
At the beginning of the protocol serves as a simple tool for obtaining information about users on the Internet. Who knows, in the bud, the internet was quite limited in the number of users, mostly it was used only “dedicated” pros and gurus. At that time there was no ICQ, Skype, even chat was not to be found is the contact information on the ip address of the person you went there was a protocol Whois.
What is the Whois

Whois is text data in which it is written that you are interested in address belong “so and so” the man is the administrator who is also (or other people), specific domain is registered by the registrar, specify the DNS addresses to which the host domain, the domain life, when he was purchased and until when will be available on the network, followed by personal data – admin contact number, e-mail for communication and even residential address. All these data can be found in whois, are in the database whois-server.

There are two options: the first – whois-server contains a complete database of all domain registrars zones (such a scheme is implemented in the domain areas: .ru, .org), otherwise – whois-server does not contain a complete database and is redirecting the request to the link between the base and the registrar of the domain zone (ie. all the information about the domain registrar is on its server, and the server whois is only a pointer to the data, an example – the zone .com). Whois protocol itself does not provide for recognition of a centralized or distributed model.

Well when whois- ¬ęclient” is able to recognize such redirection, otherwise the user will have to do everything yourself, in your hand! The determining factor model is the registrar of the domain zone, some registrars such as “dot-com” and “dotnet” are adherents of a distributed system that allows registrars to include additional fields in the records and customer information. Others registrars such as .org, using a centralized storage model registration data.

By the way, I forgot to say that the lingua franca in the whois is English and no other. Nowadays Whois implemented in software or as a web script that sends a request to the whois-server with which you can learn a specific domain is busy or available for registration. In a script is widely used on the sites domain registrars.

Whois, as in the “beginning of the way” is a tool only for “Dedication” (site owners, system administrators, web programmers), most users are not aware of its existence.