A domain name registrar is an organization that holds the central records (database) and top level authority for all the domains they administer, a single registrar is normally only responsible for 1 or 2 domain extensions like (.com or .uk). All the registrars are coordinated and partially regulated...

A domain name is a "unique" name used to identify and locate computers on the Internet. Internet domain names provide a system of easy-to-remember Internet addresses which are translated by DNS (Domain Name Servers) into numeric IP (Internet Protocol) addresses used by the Internet.
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