The WHOIS info of an domain name is a collection of many details that are freely accessed using specific lookup sites or a command line. The protocol which makes this possible bears the same name and you can very easily see the organization through which a domain name has been registered, the creation, expiration and last update dates together with the names, postal and email address of the individuals listed as Registrant (owner), Administrative, Technical and Billing contacts for a particular domain. All of this info has to be valid and up-to-date at all times; otherwise the domain registration can be challenged. The latter is a policy of ICANN (the Internet Corporation for Assigned Names and Numbers), therefore you must always make certain that the WHOIS details of your domains are legitimate. Updating the WHOIS for several country-code TLDs is limited, so any time you register a completely new domain, make sure you double-check the information that you're submitting.