What is the difference between the WhoIs information and the Domain Search functionality?

The WhoIs information provides detailed information about an existing registered Domain Name in the registrar's database. It displays all relevant information pertaining to the Domain Name. If a query is entered for a domain name that does not exist in the registrar's database, the query will check for the existence of Domain Names in other Registrars databases through the InterNIC WhoIs service, and the results are displayed. The Domain Search will simply check on the availability of registering a Domain Name. If a Domain Name is taken it will not display the Domain Name information.