The WHOIS info of a domain is a collection of numerous details which are freely accessed via special lookup sites or a command line. The protocol that makes this possible has the same name and you can easily see the company through which a domain has been registered, the creation, expiration and last update dates together with the names, postal and e-mail address of those listed as Registrant (owner), Administrative, Technical and Billing contacts for a specific Internet domain. All this info ought to be legitimate and up-to-date at all times; if it's not the domain registration could 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 addresses are valid. Updating the WHOIS for a number of country-code TLDs is limited, so any time you register a completely new domain name, you should double-check the information that you are submitting.