WHOIS actually means “Who is?” and reads the same. It’s a useful utility for looking up information on any domain name.
Whois is a widely used Internet record listing that identifies who owns a domain and how to get in contact with them. The Internet Corporation for Assigned Names and Numbers (ICANN) regulates domain name registration and ownership. Whois records have proven to be extremely useful and have developed into an essential resource for maintaining the integrity of the domain name registration and website ownership process.
It is important to note that there is no way to hide the existence of a domain registration since anyone can check Whois to confirm the status of a domain. The Internet Corporation for Assigned Names and Numbers (ICANN) requires that the contact information of those who own and manage a domain name to be made publicly available via Whois directories. This includes mailing addresses, phone numbers and email addresses.
Some domain registrars offer private registration services (also known as proxy services) in which the registrar's contact information is shown, and not that of the registrant. With this "private registration", the organization providing the domain privacy service is the domain registrant and contact. It is also important to note that even if domain privacy services are leveraged, it is not necessarily a guarantee of true anonymity. Registrars may be bound by law to release private information.
There are even a few privacy caveats with certain domain extensions, such as .us and .ca domains. As of March 2005, the National Telecommunications and Information Administration (NTIA) declared that all owners of .us domains will not have the option to privatize their information, and that it must be made publicly available. Beginning in June of 2008, the Canadian Internet Registration Authority no longer posted details of domain registrants associated with .ca domains. However, corporations and organizations are still required to publicize information.