The so-called WHOIS details of every single registered domain name include information about the registrar organization, the registration and expiration dates, in addition to the names, contact number, postal address and email address of the owner, the admin and the tech/billing person. WHOIS is a specific protocol that permits you to get all this info through a command line or via one of the many websites which provide WHOIS lookup services. All contact details ought to be up-to-date as per the regulations of ICANN, the Internet Corporation for Assigned Names and Numbers. If some of the info is not correct, the domain name may be reported and the result might be its deletion or losing its ownership. A number of country-specific domain extensions have specific limitations for the modification of their WHOIS details, but in the general scenario any detail can be changed freely and at any time. Such a change will show up on lookup websites within twenty four hours.