Domain Name Service (DNS) is a protocol which provides a mechanism to correlate all the domain names to the fundamental identification system on the Internet, IP addresses.
IP addresses are like telephone numbers. Each provides unique identification anywhere in the world.
DNS is like a telephone book. You know someone's name, so you use the telephone book to find out what their number is, then use that information to reach them.
With domain names like www.yahoo.com, you type them into your browser (Netscape or IE), then the browser uses DNS like a phone book to look up with the IP address of the domain name is, then connects you to the server with that identity.
