The WHOIS info of an domain is a collection of various details which are freely accessed through specific lookup sites or a command line. The protocol which makes this possible carries the same name and you may easily see the organization through which a domain address 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 specific domain. All this info ought to be correct and up-to-date all the time; otherwise the domain registration could be challenged. The latter is a policy of ICANN (the Internet Corporation for Assigned Names and Numbers), therefore you must always make sure that the WHOIS details of your domain addresses are valid. Updating the WHOIS for several country-code TLDs is limited, so when you register a new domain address, you should double-check the info that you are submitting.