The WHOIS information of a domain is a collection of numerous details that are publicly accessed through special lookup sites or a command line. The protocol which makes this possible carries the same name and you can easily see the firm where an Internet domain has been registered, the creation, expiration and last update dates in addition to the names, postal and email address of the individuals listed as Registrant (owner), Administrative, Technical and Billing contacts for a specific domain address. All of this info has to be valid and up-to-date constantly; if not the domain name registration can be challenged. The latter is a policy of ICANN (the Internet Corporation for Assigned Names and Numbers), therefore you should always make certain that the WHOIS details of your domains are valid. Updating the WHOIS for several country-code TLDs is limited, so whenever you register a completely new Internet domain, you should double-check the info that you are submitting.