The WHOIS information of an domain is a collection of numerous details that are freely accessed via specific lookup sites or a command line. The protocol that makes this possible has the same name and you can easily see the company where a domain address has been registered, the creation, expiration and last update dates as well as the names, postal and e-mail address of the people listed as Registrant (owner), Administrative, Technical and Billing contacts for a particular domain. All of this information has to be legitimate and up-to-date all the time; if it's not the Internet domain registration may be challenged. The latter is a policy of ICANN (the Internet Corporation for Assigned Names and Numbers), this means you must always ensure that the WHOIS details of your domain names are legitimate. Updating the WHOIS for a number of country-code TLDs is limited, so when you register a brand new Internet domain, you ought to double-check the information that you are submitting.