what is domain name?

Imagine that everybody in the world used their Social Security number or their telephone number instead of their name... If names didn't exist, you'd be forced to invent them, or you'd never be able to identify your closest friends, let alone casual acquaintances you'd met only a couple of times!

Domain names were invented to fill a similar need on the Internet. Most computers connected to the Internet are identified by a unique number called an IP address (for instance, 234.208.12.129). IP addresses are neither intuitive (they don't correspond to a geographical location as telephone number) nor easy to remember!

If you type the IP address into the URL bar of your browser you will be taken to the web site it relates to. As well as being hard to remember, however, IP addresses are also FIXED. Domain names offer a more intuitive way to name and find a website. Each domain name replaces a string of meaningless numbers (an IP address) with a simple word or expression. That's the theory - in practice, domain names can be pretty obscure too.

For example, in the URL http://www.yahoo.com/index.html, the domain name is yahoo.com.

Every domain name has a suffix that indicates which top level domain (TLD) it belongs to. There are only a limited number of such domains. For example:

gov - Government agencies

edu - Educational institutions

org - Organizations (nonprofit)

mil - Military

com - commercial business

net - Network organizations

ca - Canada

th - Thailand

Because the Internet is based on IP addresses, not domain names, every Web server requires a Domain Name System (DNS) server to translate domain names into IP addresses.