Domain Names usually have two or more parts separated by dots. Every computer that hosts data on the net has a unique address. The Domain Name System (DNS) is the important part of the Net’s technological communication. The domain name suffix is known as a generic top level domain and it describes the type of organization. For example .aero represents air-transport industry, .gov for US Government organizations, .edu for educational institutions and .com for business organizations and .coop reserved for cooperative organizations. In addition to this 244 National top level domains (NTLD) were created for countries. I will give you some examples here. They are .au for Australia, .uk for United Kingdom and .ca for Canada, etc.