What is a domain name?
Domain names are the human-friendly forms of Internet addresses, and are commonly used to find web sites. For example, the domain name bip.sx is used to locate the Bureau for Intellectual Property's web site at http://www.bip.sx
The domain name system (DNS) is essentially a global addressing system. It is the way that domain names are located and translated into Internet Protocol (IP) addresses, and vice versa. A domain name such as bip.sx is a unique alias for an IP address (a number), which is an actual physical point on the Internet.