If you type the URL
into your browser, your browser extracts the name “www.imrozbaig.com,” passes it to a domain name server, and the domain name server returns the correct IP address for www.imrozbaig.com. A number of name servers may be involved to get the right IP address. For example, in the case of www.howstuffworks.com, the name server for the “com” top-level domain will know the IP address for the name server that knows host names, and a separate query to that name server, operated by the ImrozBaig.com ISP, may deliver the actual IP address for the ImrozBaig.com server machine.
On a UNIX machine, you can access the same service using the nslookup command. Simply type a name like “www.imrozbaig.com” into the command line, and the command will query the name servers and deliver the corresponding IP address to you.
So here it is: The Internet is made up of millions of machines, each with a unique IP address. Many of these machines are server machines, meaning that they provide services to other machines on the Internet. You have heard of many of these servers: e-mail servers, Web servers, FTP servers, Gopher servers and Telnet servers, to name a few. All of these are provided by server machines.