The WHOIS info of a domain is a collection of numerous details that are openly accessed through special lookup sites or a command line. The protocol which makes this possible has the same name and you can effortlessly see the company where a domain name has been registered, the creation, expiration and last update dates together with the names, postal and e-mail address of the individuals listed as Registrant (owner), Administrative, Technical and Billing contacts for a particular domain. This info should be valid and up-to-date at all times; if not the domain registration may be challenged. The latter is a policy of ICANN (the Internet Corporation for Assigned Names and Numbers), so you should always make sure that the WHOIS details of your domain addresses are legitimate. Updating the WHOIS for a variety of country-code TLDs is limited, so whenever you register a brand new Internet domain, make sure you double-check the info you're submitting.